Answer:
[tex]71.35-2.093\frac{22.48}{\sqrt{20}}=60.83[/tex]
[tex]71.35+2.093\frac{22.48}{\sqrt{20}}=81.87[/tex]
Step-by-step explanation:
Information given
90 34 41 106 84 53 55 48 41 75 49 97 92 73 74 80 94 102 56 83
In order to calculate the mean and the sample deviation we can use the following formulas:
[tex]\bar X= \sum_{i=1}^n \frac{x_i}{n}[/tex] (2)
[tex]s=\sqrt{\frac{\sum_{i=1}^n (x_i-\bar X)}{n-1}}[/tex] (3)
[tex]\bar X=71.35[/tex] represent the sample mean for the sample
[tex]\mu[/tex] population mean (variable of interest)
s=22.48 represent the sample standard deviation
n=20 represent the sample size
Confidence interval
The confidence interval for the mean is given by the following formula:
[tex]\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}[/tex] (1)
The degrees of freedom are given by:
[tex]df=n-1=20-1=19[/tex]
Since the Confidence is 0.95 or 95%, the significance is [tex]\alpha=0.05[/tex] and [tex]\alpha/2 =0.025[/tex], and the critical value would be [tex]t_{\alpha/2}=2.093[/tex]
And replacing we got:
[tex]71.35-2.093\frac{22.48}{\sqrt{20}}=60.83[/tex]
[tex]71.35+2.093\frac{22.48}{\sqrt{20}}=81.87[/tex]
Polygon ABCD is plotted on a coordinate plane and then rotated 90 clockwise about point C to form polygon A’B’C’D Match each vertex of polygon ABCD to its coordinates.
Answer:
A' - (8,2)
B' - (5,1)
C' - (4,2)
D' - (4,5)
Step-by-step explanation:
See attachment for the missing figure.
We can see that the vertices of the polygon ABCD have coordinates A(4,6), B(5,3), C(4,2) and D(1,2)
Polygon ABCD is rotated 90° clockwise about point C to form polygon A′B′C′D′ (see attached diagram), then
A'(8,2);
B'(5,1);
C' is the same as C, thus, C'(4,2);
D'(4,5).
EASY MIDDLE SCHOOL MATH WITH INSTANT BRAINIEST AND MANY POINTS, PLZ HELP!!!
Answer:
Second option is the correct choice. See the explanation below.
Step-by-step explanation:
[tex]A=\frac{bh}{2}\\\\\mathrm{Switch\:sides}:\\\\\frac{bh}{2}=A\\\\\mathrm{Multiply\:both\:sides\:by\:}2\\\\\frac{2bh}{2}=2A\\\\hb=2A\\\\\mathrm{Divide\:both\:sides\:by\:}b;\\\\\frac{hb}{b}=\frac{2A}{b}\\\\h=\frac{2A}{b}[/tex]
Best Regards!
Answer:
[tex]h = \frac{2A}{b} [/tex]
Option B is the right option.
Solution,
[tex]a = \frac{bh}{2} \\ 2a = bh(cross \: multiplication) \\ 2a = b \times h \\ h = \frac{2A}{b} [/tex]
hope this helps...
Good luck on your assignment..
The eccentricity e of an ellipse is defined as the number c/a, where a is the distance of a vertex from the center and c is the distance of a focus from the center. Because a>c, it follows that e<1. Write a brief paragraph about the general shape of each of the following ellipses. Be sure to justify your conclusions. (a) Eccentricity close to 0 (b) Eccentricity=5 (c) Eccentricity close to 1
Answer:
Check below, please.
Step-by-step explanation:
Hi, there!
Since we can describe eccentricity as [tex]e=\frac{c}{a}[/tex]
a) Eccentricity close to 0
An ellipsis with eccentricity whose value is 0, is in fact, a degenerate one almost a circle. An ellipse whose value is close to zero is almost a degenerate circle. The closer the eccentricity comes to zero, the more rounded gets the ellipse just like a circle. (Check picture, please)
[tex]\frac{x^2}{a^2} +\frac{y^2}{b^2} =1 \:(Ellipse \:formula)\\a^2=b^2+c^2 \: (Pythagorean\: Theorem)\:a=longer \:axis.\:b=shorter \:axis)\\a^2=b^2+(0)^2 \:(c\:is \:the\: distance \: the\: Foci)\\\\a^2=b^2 \\a=b\: (the \:halves \:of \:each\:axes \:measure \:the \:same)[/tex]
b) Eccentricity =5
[tex]5=\frac{c}{a} \:c=5a[/tex]
An eccentricity equal to 5 implies that the distance between the Foci has to be five (5) times larger than the half of its longer axis! In this case, there can't be an ellipse since the eccentricity must be between 0 and 1 in other words:
[tex]If\:e=\frac{c}{a} \:then\:c>0 , and\: c>0 \:then \:1>e>0[/tex]
c) Eccentricity close to 1
In this case, the eccentricity close or equal to 1 We must conceive an ellipse whose measure for the half of the longer axis a and the distance between the Foci 'c' they both have the same size.
[tex]a=c\\\\a^2=b^2+c^2\:(In \:the\:Pythagorean\:Theorem\: we \:should\:conceive \:b=0)[/tex]
[tex]Then:\\\\a=c\\e=\frac{c}{a}\therefore e=1[/tex]
The annual interest on a $14,000 investment exceeds the interest earned on a $7000 investment by $595 . The $14,000 is invested at a 0.5% higher rate of interest than the $7000 . What is the interest rate of each investment?
Answer:
x= 8.00 Interest rate on $14000
y= 7.50 Interest rate on $7000
Step-by-step explanation:
Let interest rate of $14000 be x%
and Interest rate for $7000 be y %
According to the first condition
14000 * x% - 7000 * y% = 595
multiply by 100
14000x-7000y = 59500
/700
20x-10y=85.................(1)
II condition
x%=y%+0.5%
x=y+0.5
x-y=0.5..................................(2)
solve (1) & (2)
20 x -10 y = 85 .............1
Total value
1 x -1 y = 0.50 .............2
Eliminate y
multiply (1)by 1
Multiply (2) by -10
20.00 x -10.00 y = 85.00
-10.00 x + 10.00 y = -5.00
Add the two equations
10.00 x = 80.00
/ 10.00
x = 8.00
plug value of x in (1)
20.00 x -10.00 y = 85.00
160.00 -10.00 y = 85.00
-10.00 y = 85.00 -160.00
-10.00 y = -75.00
y = 7.50
x= 8.00 Interest rate on $14000
y= 7.50 Interest rate on $7000
Number of multiples of 7 between 200 and 1000
Answer:
114
Step-by-step explanation:
Answer:
144Step-by-step explanation:
There is more than one integer greater than 1 which leaves a reminder of1 when divided by each of the four smallest primes
Answer:
210
Complete question found at brainly(ID): 18678557 is stated below.
There is more than one integer, greater than 1, which leaves a remainder of 1 when divided by each of the four smallest primes. What is the difference between the two smallest such integers?
Step-by-step explanation:
Prime numbers are numbers that can only be divided by itself and 1
The smallest of the prime numbers we have = 2, 3, 5, 7
Since the integers greater than 1 are said to be divided by the four smallest prime numbers, we would assume the number of integers are 4 in total.
Let the integers be T
From the question:
Integer/(prime number) = quotient + (remainder/prime number)
Integer/(prime number) = Q + R/P
Let the different quotients derived from all 4 prime number = w, x, y, z
For prime 2:
T/2 = w + 1/2
T/2 - 1/2 = w
(T-1)/2 = w
T = 2w + 1
T-1 = 2w
Following the above solution
For prime 3:
T = 3x + 1
T-1 = 3x
For prime 5:
T = 5y + 1
T-1 = 5y
For prime 7:
T = 7z + 1
T-1 = 7z
T-1= T-1 = T-1 = T-1
2w = 3x = 5y = 7z
T-1 = LCM of all the prime numbers
T- 1 = 2×3×5×7
T-1 = 210
T = 210+1 = 211
T = 211
The smallest of the integer greater than 1 that leaves a remainder of 1 = 1(T-1) + 1 = 211
The next after the smallest number: 2(T-1) +1= 2(210) + 1 = 421
The two smallest number = 1(T-1) + 1 and 2(T-1) +1 respectively
The difference between the two smallest such integers = 421-211 = 210
Which is the solution to the equation 0.5 x + 4.2 = 5.9? Round to the nearest tenth if necessary. 0.9 3.4 5.1 20.2
Answer:
x = 3.4
Step-by-step explanation:
Step 1: Isolate x
0.5x = 1.7
Step 2: Divide both sides by 0.5
x = 3.4
And we have our final answer!
Answer: x=3.4
Step-by-step explanation:
[tex]0.5x+4.2=5.9[/tex]
multiply both sides by 10
[tex]5x+42=59[/tex]
subtract 42 on both sides
[tex]5x=17[/tex]
divide 5 on both sides
[tex]x=\frac{17}{5}[/tex] or
Simplify
x= 3.4
Pet Place sells pet food and supplies including a popular bailed hay for horses. When the stock of this hay drops to 20 bails, a replenishment order is placed. The store manager is concerned that sales are being lost due to stock outs while waiting for a replenishment order. It has been previously determined that demand during the lead-time is normally distributed with a mean of 15 bails and a standard deviation of 6 bails. The manager would like to know the probability of a stockout during replenishment lead-time. In other words, what is the probability that demand during lead-time will exceed 20 bails
Answer:
The probability that demand during lead-time will exceed 20 bails is 0.2033.
Step-by-step explanation:
We are given that it has been previously determined that demand during the lead-time is normally distributed with a mean of 15 bails and a standard deviation of 6 bails.
Let X = demand during the lead-time
So, X ~ Normal([tex]\mu=15, \sigma^{2} = 6^{2}[/tex])
The z-score probability distribution for the normal distribution is given by;
Z = [tex]\frac{X-\mu}{\sigma}[/tex] ~ N(0,1)
where, [tex]\mu=[/tex] population mean demand = 15 bails
[tex]\sigma[/tex] = standard deviation = 6 bails
Now, the probability that demand during lead-time will exceed 20 bails is given by = P(X > 20 bails)
P(X > 20 bails) = P( [tex]\frac{X-\mu}{\sigma}[/tex] > [tex]\frac{20-15}{6}[/tex] ) = P(Z > 0.83) = 1 - P(Z [tex]\leq[/tex] 0.83)
= 1 - 0.7967 = 0.2033
What is the slope of the line with the two
points A(-4, 8) and B(-9, 12)?
Answer:
slope = -4/5
Step-by-step explanation:
A line passes two points (x1, y1) and (x2, y2).
The slope of this line can be calculate by the formula:
s = (y2 - y1)/(x2 - x1)
=>The line that passes A(-4, 8) and B(-9, 12) has the slope:
s = (12 - 8)/(-9 - -4) = 4/(-5) = -4/5
Hope this helps!
Suppose that four microchips in a production run of sixty are defective. A sample of six is to be selected to be checked for defects. (a) How many different samples can be chosen
Answer:
50,063,860 different samples can be chosen
Step-by-step explanation:
The order in which the microchips are chosen is not important. So we use the combinations formula to solve this question.
Combinations formula:
[tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
How many different samples can be chosen
We choose 6 microchips from a set of 60. So
[tex]C_{60,6} = \frac{60!}{6!(60-6)!} = 50063860[/tex]
50,063,860 different samples can be chosen
6. Factor the expression.
9b2 + 48b + 64
A (3b + 8)2
B (-3b + 8)2
C (-3b - 82
D (3b - 8)2
70%
Answer:
A. [tex](3b+8)^2[/tex]
Step-by-step explanation:
[tex]9b^2+48b +64\\=(3b)^2 + 2\times 3b\times 8 +(8)^2\\=(3b+8)^2[/tex]
The mean number of hours of part-time work per week for a sample of 317 teenagers is 29. If the margin of error for the population mean with a 95% confidence interval is 2.1, construct a 95% confidence interval for the mean number of hours of part-time work per week for all teenagers.
Answer:
The degrees of freedom are given by:
[tex]df=n-1=317-1=316[/tex]
And replaicing we got:
[tex]29-2.1=26.9[/tex]
[tex]29+2.1=31.1[/tex]
The 95% confidence interval would be between 26.9 and 31.1
Step-by-step explanation:
Information given
[tex]\bar X= 29[/tex] represent the sample mean
[tex]\mu[/tex] population mean
s represent the sample standard deviation
[tex] ME= 2.1[/tex] represent the margin of error
n represent the sample size
Solution
The confidence interval for the mean is given by the following formula:
[tex]\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}[/tex] (1)
And this formula is equivalent to:
[tex] \bar X \pm ME[/te]x
The degrees of freedom are given by:
[tex]df=n-1=317-1=316[/tex]
And replaicing we got:
[tex]29-2.1=26.9[/tex]
[tex]29+2.1=31.1[/tex]
The 95% confidence interval would be between 26.9 and 31.1
A school librarian purchases a novel for her library. The publisher claims that the book is written at a 5th grade reading level, but the librarian suspects that the reading level is higher than that. The librarian selects a random sample of 40 pages and uses a standard readability test to assess the reading level of each page. The mean reading level of these pages is 5.2 with a standard deviation of 0.8. Do these data give convincing evidence at the = 0.05 significance level that the average reading level of this novel is greater than 5?
Answer:
[tex]t=\frac{5.2-5}{\frac{0.8}{\sqrt{40}}}=1.58[/tex]
The degrees of freedom are given by:
[tex]df=n-1=40-1=39[/tex]
Thep value for this case would be given by:
[tex]p_v =P(t_{(39)}>1.58)=0.061[/tex]
Since the p value is higher than the significance level of 0.05 we have enough evidence to FAIL to reject the null hypothesis and we can conclude that true mean is not significantly higher than 5.
Step-by-step explanation:
Information provided
[tex]\bar X=5.2[/tex] represent the sample mean
[tex]s=0.8[/tex] represent the sample standard deviation
[tex]n=40[/tex] sample size
[tex]\mu_o =5[/tex] represent the value to verify
[tex]\alpha=0.05[/tex] represent the significance level
t would represent the statistic
[tex]p_v[/tex] represent the p value
Hypothesis to test
We want to verify if the true mean is higher than 5, the system of hypothesis would be:
Null hypothesis:[tex]\mu \leq 5[/tex]
Alternative hypothesis:[tex]\mu > 5[/tex]
The statistic is given by:
[tex]t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}[/tex] (1)
Replacing the info given we got:
[tex]t=\frac{5.2-5}{\frac{0.8}{\sqrt{40}}}=1.58[/tex]
The degrees of freedom are given by:
[tex]df=n-1=40-1=39[/tex]
Thep value for this case would be given by:
[tex]p_v =P(t_{(39)}>1.58)=0.061[/tex]
Since the p value is higher than the significance level of 0.05 we have enough evidence to FAIL to reject the null hypothesis and we can conclude that true mean is not significantly higher than 5.
Lara’s Inc. is currently an unlevered firm with 450,000 shares of stock outstanding, with a market price of $15 a share. The company has earnings before interest and taxes of $314,000. Lara's met with his bankers, Warne Incorporated and agreed to borrow $825,000, at 5 percent. You are an ardent investor and you currently own 20,000 shares of Lara's stock. If you seek to unlevered your position; how many shares of Lara's stock will you continue to own, if you can loan out funds at 5 percent interest? Ignore taxes in your deliberations. Kindly show all workings.
Answer:
tiStep-by-step explanaon:
pls helppppp with my math
Answer:
[tex]\frac{1}{6}[/tex]
Step-by-step explanation:
Answer:
Step-by-step explanation:
[tex]\frac{5}{6}-\frac{2}{3}=\frac{5}{6}-\frac{2*2}{3*2}\\\\=\frac{5}{6}-\frac{4}{6}\\\\=\frac{5-4}{6}\\\\=\frac{1}{6}[/tex]
The amount of pollutants that are found in waterways near large cities is normally distributed with mean 8.5 ppm and standard deviation 1.4 ppm. 18 randomly selected large cities are studied. Round all answers to two decimal places.
A. xBar~ N( ____) (____)
B. For the 18 cities, find the probability that the average amount of pollutants is more than 9 ppm.
C. What is the probability that one randomly selected city's waterway will have more than 9 ppm pollutants?
D. Find the IQR for the average of 18 cities.Q1 =
Q3 =
IQR:
2. X ~ N(30,10). Suppose that you form random samples with sample size 4 from this distribution. Let xBar be the random variable of averages. Let ΣX be the random variable of sums. Round all answers to two decimal places.
A. xBar~ N(___) (____)
B. P(xBar<30) =
C. Find the 95th percentile for the xBar distribution.
D. P(xBar > 36)=
E. Q3 for the xBar distribution =
Answer:
1)
A) [tex]\frac{}{X}[/tex] ~ N(8.5;0.108)
B) P([tex]\frac{}{X}[/tex] > 9)= 0.0552
C) P(X> 9)= 0.36317
D) IQR= 0.4422
2)
A) [tex]\frac{}{X}[/tex] ~ N(30;2.5)
B) P( [tex]\frac{}{X}[/tex]<30)= 0.50
C) P₉₅= 32.60
D) P( [tex]\frac{}{X}[/tex]>36)= 0
E) Q₃: 31.0586
Step-by-step explanation:
Hello!
1)
The variable of interest is
X: pollutants found in waterways near a large city. (ppm)
This variable has a normal distribution:
X~N(μ;σ²)
μ= 8.5 ppm
σ= 1.4 ppm
A sample of 18 large cities were studied.
A) The sample mean is also a random variable and it has the same distribution as the population of origin with exception that it's variance is affected by the sample size:
[tex]\frac{}{X}[/tex] ~ N(μ;σ²/n)
The population mean is the same as the mean of the variable
μ= 8.5 ppm
The standard deviation is
σ/√n= 1.4/√18= 0.329= 0.33 ⇒σ²/n= 0.33²= 0.108
So: [tex]\frac{}{X}[/tex] ~ N(8.5;0.108)
B)
P([tex]\frac{}{X}[/tex] > 9)= 1 - P([tex]\frac{}{X}[/tex] ≤ 9)
To calculate this probability you have to standardize the value of the sample mean and then use the Z-tables to reach the corresponding value of probability.
Z= [tex]\frac{\frac{}{X} - Mu}{\frac{Sigma}{\sqrt{n} } } = \frac{9-8.5}{0.33}= 1.51[/tex]
Then using the Z table you'll find the probability of
P(Z≤1.51)= 0.93448
Then
1 - P([tex]\frac{}{X}[/tex] ≤ 9)= 1 - P(Z≤1.51)= 1 - 0.93448= 0.0552
C)
In this item, since only one city is chosen at random, instead of working with the distribution of the sample mean, you have to work with the distribution of the variable X:
P(X> 9)= 1 - P(X ≤ 9)
Z= (X-μ)/δ= (9-8.5)/1.44
Z= 0.347= 0.35
P(Z≤0.35)= 0.63683
Then
P(X> 9)= 1 - P(X ≤ 9)= 1 - P(Z≤0.35)= 1 - 0.63683= 0.36317
D)
The first quartile is the value of the distribution that separates the bottom 2% of the distribution from the top 75%, in this case it will be the value of the sample average that marks the bottom 25% symbolically:
Q₁: P([tex]\frac{}{X}[/tex]≤[tex]\frac{}{X}[/tex]₁)= 0.25
Which is equivalent to the first quartile of the standard normal distribution. So first you have to identify the first quartile for the Z dist:
P(Z≤z₁)= 0.25
Using the table you have to identify the value of Z that accumulates 0.25 of probability:
z₁= -0.67
Now you have to translate the value of Z to a value of [tex]\frac{}{X}[/tex]:
z₁= ([tex]\frac{}{X}[/tex]₁-μ)/(σ/√n)
z₁*(σ/√n)= ([tex]\frac{}{X}[/tex]₁-μ)
[tex]\frac{}{X}[/tex]₁= z₁*(σ/√n)+μ
[tex]\frac{}{X}[/tex]₁= (-0.67*0.33)+8.5= 8.2789 ppm
The third quartile is the value that separates the bottom 75% of the distribution from the top 25%. For this distribution, it will be that value of the sample mean that accumulates 75%:
Q₃: P([tex]\frac{}{X}[/tex]≤[tex]\frac{}{X}[/tex]₃)= 0.75
⇒ P(Z≤z₃)= 0.75
Using the table you have to identify the value of Z that accumulates 0.75 of probability:
z₃= 0.67
Now you have to translate the value of Z to a value of [tex]\frac{}{X}[/tex]:
z₃= ([tex]\frac{}{X}[/tex]₃-μ)/(σ/√n)
z₃*(σ/√n)= ([tex]\frac{}{X}[/tex]₃-μ)
[tex]\frac{}{X}[/tex]₃= z₃*(σ/√n)+μ
[tex]\frac{}{X}[/tex]₃= (0.67*0.33)+8.5= 8.7211 ppm
IQR= Q₃-Q₁= 8.7211-8.2789= 0.4422
2)
A)
X ~ N(30,10)
For n=4
[tex]\frac{}{X}[/tex] ~ N(μ;σ²/n)
Population mean μ= 30
Population variance σ²/n= 10/4= 2.5
Population standard deviation σ/√n= √2.5= 1.58
[tex]\frac{}{X}[/tex] ~ N(30;2.5)
B)
P( [tex]\frac{}{X}[/tex]<30)
First you have to standardize the value and then look for the probability:
Z= ([tex]\frac{}{X}[/tex]-μ)/(σ/√n)= (30-30)/1.58= 0
P(Z<0)= 0.50
Then
P( [tex]\frac{}{X}[/tex]<30)= 0.50
Which is no surprise since 30 y the value of the mean of the distribution.
C)
P( [tex]\frac{}{X}[/tex]≤ [tex]\frac{}{X}[/tex]₀)= 0.95
P( Z≤ z₀)= 0.95
z₀= 1.645
Now you have to reverse the standardization:
z₀= ([tex]\frac{}{X}[/tex]₀-μ)/(σ/√n)
z₀*(σ/√n)= ([tex]\frac{}{X}[/tex]₀-μ)
[tex]\frac{}{X}[/tex]₀= z₀*(σ/√n)+μ
[tex]\frac{}{X}[/tex]₀= (1.645*1.58)+30= 32.60
P₉₅= 32.60
D)
P( [tex]\frac{}{X}[/tex]>36)= 1 - P( [tex]\frac{}{X}[/tex]≤36)= 1 - P(Z≤(36-30)/1.58)= 1 - P(Z≤3.79)= 1 - 1 = 0
E)
Q₃: P([tex]\frac{}{X}[/tex]≤[tex]\frac{}{X}[/tex]₃)= 0.75
⇒ P(Z≤z₃)= 0.75
z₃= 0.67
z₃= ([tex]\frac{}{X}[/tex]₃-μ)/(σ/√n)
z₃*(σ/√n)= ([tex]\frac{}{X}[/tex]₃-μ)
[tex]\frac{}{X}[/tex]₃= z₃*(σ/√n)+μ
[tex]\frac{}{X}[/tex]₃= (0.67*1.58)+30= 31.0586
Q₃: 31.0586
Find the area of the smaller sector.
A
6 in
030°
Area = [? ]in?
B
Round your answer to the nearest hundredth.
Answer:
9.42 in²
Step-by-step explanation:
The area of whole circle S=pi*R² , where pi is appr. 3.14, R= 6 in
S= 3.14*6² =113.04 in²
The area of smaller sector is Ssec=S/360*30=113,04/12=9.42 in²
The area of the smaller sector with a central angle of 30 degrees and a radius of 6 inches is 9.42478 square inches.
To find the area of a sector, you can use the formula:
Area of sector = (θ/360) × π × r²
where θ is the central angle in degrees, r is the radius of the sector.
The central angle is 30 degrees and the radius is 6 inches.
Plugging these values into the formula:
Area of sector = (30/360) × π × 6²
= (1/12) × π × 36
= (1/12) × 3.14159 × 36
= 9.42478 square inches
To learn more on Area of sector click:
https://brainly.com/question/29055300
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Which equation represents a parabola that opens upward, has a minimum at x = 3, and has a line of symmetry at x = 3?
A. y = x^2 - 6x + 13
B. y = x^2 - 8x + 19
C. y= x^2 - 3x + 6
D. y= x^2 + 6x + 5
Answer:
[tex]A.\ y = x^2 - 6x + 13[/tex] is the correct answer.
Step-by-step explanation:
We know that vertex equation of a parabola is given as:
[tex]y = a(x-h)^2+k[/tex]
where [tex](h,k)[/tex] is the vertex of the parabola and
[tex](x,y)[/tex] are the coordinate of points on parabola.
As per the question statement:
The parabola opens upwards that means coefficient of [tex]x^{2}[/tex] is positive.
Let [tex]a = +1[/tex]
Minimum of parabola is at x = 3.
The vertex is at the minimum point of a parabola that opens upwards.
[tex]\therefore[/tex] [tex]h = 3[/tex]
Putting value of a and h in the equation:
[tex]y = 1(x-3)^2+k\\\Rightarrow y = (x-3)^2+k\\\Rightarrow y = x^2-6x+9+k[/tex]
Formula used: [tex](a-b)^2=a^{2} +b^{2} -2\times a \times b[/tex]
Comparing the equation formulated above with the options given we can observe that the equation formulated above is most similar to option A.
Comparing [tex]y = x^2 - 6x + 13[/tex] and [tex]y = x^2-6x+9+k[/tex]
13 = 9+k
k = 4
Please refer to the graph attached.
Hence, correct option is [tex]A.\ y = x^2 - 6x + 13[/tex]
Answer:
A. y = x^2 -6x + 13
Step-by-step explanation:
What is the result of −18⋅16 2/3? Enter the result as an improper fraction and as a mixed number.
Answer:
-30000/100
300 0/1
Step-by-step explanation:
We have the following numbers -18 and 16 2/3, the first is an integer and the second is a mixed number, the first thing is to pass the mixed number to a decimal number.
16 2/3 = 16.67
We do the multiplication:
−18⋅16 2/3 = -300
We have an improper fraction is a fraction in which the numerator (top number) is greater than or equal to the denominator (bottom number), therefore it would be:
-30000/100
How mixed number would it be:
300 0/1
Please help Solving linear and quadratic equations
Answer: B.
x ≈2.5
Step-by-step explanation:
[tex]-\left(u\right)^{-1}-6=-u+10[/tex]
[tex]u=8-\sqrt{65},\:u=8+\sqrt{65}[/tex]
[tex]x=\frac{\ln \left(8+\sqrt{65}\right)}{\ln \left(3\right)}[/tex]
x=2.52...
Answer:
x=2.5
Step-by-step explanation:
A consumer group was interested in comparing the operating time of cordless toothbrushes manufactured by two different companies. Group members took a random sample of 18 toothbrushes from Company A and 15 from Company B. Each was charged overnight and the number of hours of use before needing to be recharged was recorded. Company A toothbrushes operated for an average of 119.7 hours with a standard deviation of 1.74 hours; Company B toothbrushes operated for an average of 120.6 hours with a standard deviation of 1.72 hours. The 90% confidence interval is (-1.93, 0.13). The correct interpretation is:__________
A. We are 90% confident that, on average, there is no difference in operating hours between toothbrushes from Company A compared to those from Company B.
B. We are 90% confident that, on average, there is a difference in operating hours between toothbrushes from Company A compared to those from Company B.
C. We are 90% confident that, on average, the toothbrushes from Company B operate longer before needing to be recharged than the toothbrushes from Company A.
D. We are 90% confident that, on average, the toothbrushes from Company A operate longer before needing to be recharged than the toothbrushes from Company B.
Answer:
The degrees of freedom are given by:
[tex] df = n_A +n_B -2 = 18 +15-2= 31[/tex]
And the 90% confidence interval for this case is:
[tex] -1.90 \leq \mu_A -\mu_B \leq 0.13[/tex]
And for this case since the confidence interval contains the value 0 we can conclude that:
A. We are 90% confident that, on average, there is no difference in operating hours between toothbrushes from Company A compared to those from Company B.
Step-by-step explanation:
We know the following info given:
[tex] \bar X_A= 119.7[/tex] sample mean for A
[tex] s_A = 1.74[/tex] sample deviation for A
[tex] n_A = 18[/tex] sample size from A
[tex] \bar X_B= 120.6[/tex] sample mean for B
[tex] s_B = 1.72[/tex] sample deviation for B
[tex] n_B = 15[/tex] sample size from B
The degrees of freedom are given by:
[tex] df = n_A +n_B -2 = 18 +15-2= 31[/tex]
And the 90% confidence interval for this case is:
[tex] -1.90 \leq \mu_A -\mu_B \leq 0.13[/tex]
And for this case since the confidence interval contains the value 0 we can conclude that:
A. We are 90% confident that, on average, there is no difference in operating hours between toothbrushes from Company A compared to those from Company B.
Determine the present value P that must be invested to have the future value A at simple interest rate r after time t. A = $7000.00, r = 9.5%, t = 9 months
Answer:
$6534.42
Step-by-step explanation:
Put the given values into the simple interest formula and solve for the remaining variable.
A = P(1 +rt)
where P is the principal invested, r is the annual rate, and t is the number of years.
$7000 = P(1 +0.095(9/12)) = 1.07125P
$7000/1.07125 = P ≈ $6534.42
The value that must be invested is $6534.42.
Alan has reached 25% of his weekly exercise time goal so far this week. If he has exercised for a total of 42 minutes this week, what is his weekly exercise time goal in minutes
Answer:
His weekly exercise time goal is 168 minutes.
Step-by-step explanation:
This question can be solved using a rule of three.
42 minutes is 25% = 0.25 of the total
x minutes is 100% = 1 of the total.
Then
42 minutes - 0.25
x minutes - 1
[tex]0.25x = 42[/tex]
[tex]x = \frac{42}{0.25}[/tex]
[tex]x = 168[/tex]
His weekly exercise time goal is 168 minutes.
ali's typing rate between 8:00 am and noon is 48 words per minute . after lunch a lunch break, Ali's typing rate between 1:00 pm and 4:00 pm is 2,040 words per hour . what is Ali's average typing rate per minute for the whole time she works?
Answer:
41 word/min
Step-by-step explanation:
Before noon Ali works:
4 hours= 4*60 min= 240 minShe types:
240*48= 11520 wordsAfter lunch she works:
4 hoursShe types:
4*2040= 8160 wordsTotal Ali works= 4+4= 8 hours= 480 min
Total Ali types= 11520+8160= 19680 words
Average typing rate= 19680 words/480 min= 41 word/min
1. A random sample of 64 customers at a drive-through bank window is observed, and it is found that the teller spends an average of 2.8 minutes with each customer, with a standard deviation of 1.2 minutes. Is there sufficient evidence to conclude that the teller spends less than 3 minutes with each customer
Answer:
The 95% confidence interval is 2.5 < u <3.1.
Step-by-step explanation:
The provided sample mean is X = 2.8 and the sample standard deviation is s = 1.2, and the sample size is n = 64.
1. Null and Alternative Hypotheses:
The following null and alternative hypotheses need to be tested:
H0 u = 3
Ha: u < 3
This corresponds to a left-tailed test, for which a t-test for one mean, with unknown population standard deviation will be used.
2. Rejection Region Based
on the information provided, the significance level is alpha = 0.05, and the critical value for a left-tailed test is t c = -1.669.
The rejection region for this left-tailed test is R = t : t < -1.669
3. Test Statistics
The t-statistic is computed as follows:
t = (X - uo)/[s/n^(1/2)] =
replacing
t = (2.8 - 3)/ [1.2/64 ^(1/2)]
t =-1.333
4. Decision about the null hypothesis
Since it is observed that t = -1.333 > t c = -1.669, it is then concluded that the null hypothesis is not rejected.
Using the P-value approach: The p-value is p = 0.0936, and since p= 0.0936 => 0.05, it is concluded that the null hypothesis is not rejected.
5. Conclusion It is concluded that the null hypothesis H0 is not rejected. Therefore, there is not enough evidence to claim that the population mean u is less than 3, at the 0.05 significance level.
Confidence Interval
The 95% confidence interval is 2.5 < u <3.1.
Find the area of a triangle that has the base of 5 inches and a height of 3 3/4 inches
Answer:
9.375 in^2
Step-by-step explanation:
Two types of shipping boxes are shown below. What is the difference in the surface areas, in square feet, of the two boxes
*see attachment showing the 2 boxes
Answer:
3 ft²
Step-by-step explanation:
==>Given:
Box J with the following dimensions:
L = 4.5ft
W = 3ft
H = 2ft
Box F:
L = 3ft
W = 3ft
H = 3ft
==>Required:
Difference between the surface area of box J and box F
==>Solution:
Surface area = 2(WL + HL + HW)
=>S.A of box J = 2(3*4.5 + 2*4.5 + 2*3)
= 2(13.5 + 9 + 6)
= 2(28.5)
S.A of box J = 57 ft²
=>S.A of box F = 2(3*3 + 3*3 + 3*3)
= 2(9 + 9 + 9)
= 2(27)
S.A of box F = 54 ft²
Difference between box J and box F = 57 - 54 = 3 ft²
The World Issues club has decided to donate 60% of all their fundraising activities this year to Stephen Lewis Foundation. This foundation was created to help ease the pain of HIV/AIDS in Africa. Lewis, a Canadian, works for the United Nations trying to determine ways to stop the spread of this deadly disease from crippling an entire continent. Choose a variable to represent the money earned during fundraising activities and the revenue generated for the foundation Use these variables to create an equation that will determine the amount of money the foundation will receive. In their latest bake sale, the club raised $72. Calculate the amount the foundation will receive. At the end of the year, the World Issues Club mailed a cheque to the foundation for $850. How much money did they fundraise in total?
Answer:
$43.20$1416.67Step-by-step explanation:
Let the money earned during fundraising activities =x
Since the World Issues club has decided to donate 60% of all their fundraising activities this year to Stephen Lewis Foundation.
The amount of money the foundation will receive
=60% of x
= 0.6x
In the bake sale, the club raised $72.
Therefore, the amount the foundation will receive =0.6*72=$43.20
At the end of the year, the World Issues Club mailed a cheque to the foundation for $850.
Therefore:
0.6x=850
x=850/0.6
x=$1416.67
The total amount of money the club raised is $1416.67.
Someone flips five coins, but you don’t see the outcome. The person reports that no tails are showing. What is the probability that the person flipped 5 heads?
Answer:
0.03125 = 3.125% probability that the person flipped 5 heads
Step-by-step explanation:
For each coin, there are only two possible outcomes. Either it was heads, or it was tails. The result of a coin toss is independent of other coin tosses. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
Five coins:
This means that n = 5.
Fair coin:
Equally as likely to be heads or tails, so p = 0.5.
What is the probability that the person flipped 5 heads?
This is P(X = 5).
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 5) = C_{5,5}.(0.5)^{5}.(0.5)^{0} = 0.03125[/tex]
0.03125 = 3.125% probability that the person flipped 5 heads
Two thousand dollars is deposited into a savings account at 8.5% interest compounded continuously. (a) What is the formula for A(t), the balance after t years? (b) What differential equation is satisfied by A(t), the balance after t years? (c) How much money will be in the account after 5 years? (d) When will the balance reach $3000? (e) How fast is the balance growing when it reaches $3000?
Answer:
a)[tex]A(t)=2000e^{0.085t}[/tex]
b)[tex]A'(t)=170e^{0.085t}[/tex]
c)$3059.1808
d)t=4.77 years
e) The balance growing is $254.99/year
Step-by-step explanation:
We are given that Two thousand dollars is deposited into a savings account at 8.5% interest compounded continuously.
Principal = $2000
Rate of interest = 8.5%
a) What is the formula for A(t), the balance after t years?
Formula [tex]A(t)=Pe^{rt}[/tex]
So,[tex]A(t)=2000e^{0.085t}[/tex]
B)What differential equation is satisfied by A(t), the balance after t years?
So, [tex]A'(t)=2000 \times 0.085 e^{0.085t}[/tex]
[tex]A'(t)=170e^{0.085t}[/tex]
c)How much money will be in the account after 5 years?
Substitute t = 5 in the formula "
[tex]A(t)=2000e^{0.085t}\\A(5)=2000e^{0.085(5)}\\A(5)=3059.1808[/tex]
d)When will the balance reach $3000?
Substitute A(t)=3000
So, [tex]3000=2000e^{0.085t}[/tex]
t=4.77
The balance reach $3000 in 4.77 years
e)How fast is the balance growing when it reaches $3000?
Substitute the value of t = 4.77 in derivative formula :
[tex]A'(t)=170e^{0.085t}\\A'(t)=170e^{0.085 \times 4.77}\\A'(t)=254.99[/tex]
Hence the balance growing is $254.99/year