Answer:
Step-by-step explanation:
This is a test of 2 independent groups. Let μ1 be the mean score of Mrs. Smith's students and μ2 be the mean score of Mrs. Jones students.
The random variable is μ1 - μ2 = difference in the mean score of Mrs. Smith's students and the mean score of Mrs. Jones students.
We would set up the hypothesis.
The null hypothesis is
H0 : μ1 = μ2 H0 : μ1 - μ2 = 0
The alternative hypothesis is
H1 : μ1 ≠ μ2 H1 : μ1 - μ2 ≠ 0
This is a two tailed test.
The formula for determining the degree of freedom is
df = [s1²/n1 + s2²/n2]²/(1/n1 - 1)(s1²/n1)² + (1/n2 - 1)(s2²/n2)²
From the information given,
μ1 = 78
μ2 = 85
s1 = 10
s2 = 15
n1 = 30
n2 = 25
df = [10²/30 + 15²/25]²/[(1/30 - 1)(10²/30)² + (1/25 - 1)(15²/25)²] = 152.11/3.37883141762
df = 45
Since sample standard deviation is known, we would determine the test statistic by using the t test. The formula is
(x1 - x2)/√(s1²/n1 + s2²/n2)
t = (78 - 85)/√(10²/30 + 15²/25)
t = - 1.99
d) Confidence interval = μ1 - μ2 ± z√(s1²/n1 + s2²/n2)
Where z is the t test score for the confidence level. Since alpha = 0.1, confidence level = 1 - alpha = 1 - 0.1 = 0.9. From the t distribution table, test score at df of 45 = 1.301
z√(s1²/n1 + s2²/n2) = 1.301√(10²/30 + 15²/25) = 4.57
Confidence interval = (78 - 85) ± 4.57
Confidence interval = - 7 ± 4.57
e) we would find the critical value corresponding to 1 - α/2 and reject the null hypothesis if the absolute value of the test statistic is greater than the value of t 1 - α/2 from the table.
1 - α/2 = 1 - 0.1/2 = 1 - 0.05 = 0.95
The critical value is 1.679 on the right tail and - 1.679 on the left tail
Since - 1.99 < - 1.679, it is not in the rejection regions. Therefore, we would fail to reject the null hypothesis. Therefore, at 10% significance level, there is insufficient evidence to conclude that Mrs. Smith and Mrs. Jones are not equally effective teachers.
Which one of the following groups of numbers includins all prime numbers? a)2,3,5 b)7,17,63,67 c)3,11,63,67 d)1,3,11,23
Answer:
a) 2, 3, 5
Step-by-step explanation:
2, 3, 5
All numbers are prime.
7, 17, 63, 67
63 is not a prime number.
3, 11, 63, 67
63 is not a prime number.
1, 3, 11, 23
1 is not a prime number.
Write the numbers in scientific notation.
8. 5,100,000
9. .00000698
10. 3.000052
Write the numbers in standard form.
11. 6.548 x 10-3
12. 5.854 x 10' 58.54
13. 2.25 x 106
Answer:
8)5.1*10⁶
9)6.98*10 to the power of -6
10) 3.000052*10⁰
11)0.006548
How many gallons of 20% moonshine and how many gallons of 30% moonshine have to be mixed together to make 100 gallons of 28% moonshine? x = gallons of 20% moonshine y = gallons of 30% moonshine
Answer:
20 and 80
Step-by-step explanation:
x+y= 100
0.2x+0.3y= 0.28*100
0.2x+0.3*(100-x)= 280.2x- 0.3x +30= 280.1x= 2x= 20 ⇒ y= 80
Chang knows one side of a triangle is 13 cm. Which set of two sides is possible for the lengths of the other two side
bf this triangle?
O 5 cm and 8 cm
O 6 cm and 7 cm
O 7 cm and 2 cm
8 cm and 9 cm
Answer:
It's (D) 8 cm and 9 cm. Hope this helps you!
Step-by-step explanation:
The other 2 sides added have to be greater than 13.
Answer:
8 and 9
Step-by-step explanation:
The triangle inequality states that the sum of the two shortest sides must be greater than the longest side.
Let's check the first one. 5 + 8 > 13 → 13 > 13 which is false.
6 + 7 > 13 → 13 > 13 which is false.
7 + 2 > 13 → 9 > 13 which is false.
8 + 9 > 13 → 17 > 13 which is true.
Manuel ordered pizza for a party. A vegetable pizza has 6 slices per pie. A cheese pizza has 8 slices per pie. Manuel ordered four times as many cheese pizzas as vegetable pizzas, for a total of 152 slices. How many pizzas did Manuel order? 15 20 30 40
Answer:
20 Pizza
Step-by-step explanation:
Let the number of vegetable pizza be x
Given that
Manuel ordered four times as many cheese pizzas as vegetable pizzas
the number of cheese pizza = 4x
1. no of slice in 1 vegetable pizza pie = 6
no of slice in x vegetable pizza pie = 6x
2. no of slice in 1 cheese pizza pie = 8
no of slice in 4x cheese pizza pie = 8*4x = 32x
Total no of slice for x vegetable pizza and 4x cheese pizza = 6x+32x = 38x
Given that
total no. of 152 slices, therefore
38x = 152
=> x = 152/38 = 4
Thus, no. of vegetable pizza ordered = 4
no. of cheese pizza ordered = 4x = 4*$ = 16
Total no of pizza ordered = 16+4 = 20 (answer)
Answer:
B
Step-by-step explanation:
Which function models the geometric sequence in the table?
Hope you understand :)
Need some help on this whole unit to be honest but any help with this one ?
answer:
i believe they all are identical
Step-by-step explanation:
i used a website called desmos graphing calculator and typed each one out and this is what it looked like
PLSSSSSSS HELP WILL MARK BRAINLIEST Doug owns a lawn mowing and landscaping business. The income from the business is given by the function f(x) = 2x + 54, where f(x) is the income in dollars and x is the area in square meters of lawn mowed. If he has earned {204, 344, 450, 482} dollars in the last four months, what are the corresponding areas of lawn he mowed?
Answer:
i think this person answered but idrk perseusharrison79
Step-by-step explanation:
For 2 parallelograms, the corresponding side lengths are 1 inch and x inches, and 2 inches and 6 inches.
Not drawn to scale
StartFraction 1 over x EndFraction = StartFraction 2 over 6 EndFraction
StartFraction 1 over x EndFraction = StartFraction 6 over 2 EndFraction
StartFraction 1 over 6 EndFraction = StartFraction 2 over x EndFraction
One-half = StartFraction 6 over x EndFraction
Step-by-step explanation:
Is the sequence arithmetic? If so, how do you know? Given the sequence: 20, 26, 32, 38, . . .
Answer:
yes
Step-by-step explanation:
it is
because difference between each two consecutive terms are equal
26-20=32-26=38-32
for the formula:
20 is the first term.
6 is the difference between each two consecutive terms
so:
[tex]y = 6(x - 1) + 20 \\ y = 6x + 14[/tex]
A random sample of soil specimens was obtained, and the amount of organic matter (%) in the soil was determined for each specimen, resulting in the accompanying data (from "Engineering Properties of Soil," Soil Science, 1998: 93–102).1.10 5.09 0.97 1.59 4.60 0.32 0.55 1.450.14 4.47 1.20 3.50 5.02 4.67 5.22 2.693.98 3.17 3.03 2.21 0.69 4.47 3.31 1.170.76 1.17 1.57 2.62 1.66 2.05The values of the sample mean, sample standard deviation,and (estimated) standard error of the mean are2.481, 1.616, and .295, respectively. Does this data suggestthat the true average percentage of organic matterin such soil is something other than 3%? Carry out atest of the appropriate hypotheses at significance level.10. Would your conclusion be different if a 5 .05 hadbeen used? [Note: A normal probability plot of the datashows an acceptable pattern in light of the reasonablylarge sample size.]
Answer:
We conclude that the true average percentage of organic matter in such soil is something other than 3% at 10% significance level.
We conclude that the true average percentage of organic matter in such soil is 3% at 5% significance level.
Step-by-step explanation:
We are given a random sample of soil specimens was obtained, and the amount of organic matter (%) in the soil was determined for each specimen;
1.10, 5.09, 0.97, 1.59, 4.60, 0.32, 0.55, 1.45, 0.14, 4.47, 1.20, 3.50, 5.02, 4.67, 5.22, 2.69, 3.98, 3.17, 3.03, 2.21, 0.69, 4.47, 3.31, 1.17, 0.76, 1.17, 1.57, 2.62, 1.66, 2.05.
Let [tex]\mu[/tex] = true average percentage of organic matter
So, Null Hypothesis, [tex]H_0[/tex] : [tex]\mu[/tex] = 3% {means that the true average percentage of organic matter in such soil is 3%}
Alternate Hypothesis, [tex]H_A[/tex] : [tex]\mu \neq[/tex] 3% {means that the true average percentage of organic matter in such soil is something other than 3%}
The test statistics that will be used here is One-sample t-test statistics because we don't know about the population standard deviation;
T.S. = [tex]\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }[/tex] ~ [tex]t_n_-_1[/tex]
where, [tex]\bar X[/tex] = sample mean percentage of organic matter = 2.481%
s = sample standard deviation = 1.616%
n = sample of soil specimens = 30
So, the test statistics = [tex]\frac{2.481-3}{\frac{1.616}{\sqrt{30} } }[/tex] ~ [tex]t_2_9[/tex]
= -1.76
The value of t-test statistics is -1.76.
(a) Now, at 10% level of significance the t table gives a critical value of -1.699 and 1.699 at 29 degrees of freedom for the two-tailed test.
Since the value of our test statistics doesn't lie within the range of critical values of t, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region.
Therefore, we conclude that the true average percentage of organic matter in such soil is something other than 3% at 10% significance level.
(b) Now, at 5% level of significance the t table gives a critical value of -2.045 and 2.045 at 29 degrees of freedom for the two-tailed test.
Since the value of our test statistics lies within the range of critical values of t, so we have insufficient evidence to reject our null hypothesis as it will not fall in the rejection region.
Therefore, we conclude that the true average percentage of organic matter in such soil is 3% at 5% significance level.
Simplify the expression. 641/3
Answer:213.7
Step-by-step explanation:
1. For some constant c, the random variable X has probability density function
cx", 0
0, otherwise.
What is the value of c?
a) 1/n;
b) na ;
c)n + 1;
d) n;
e) n–1.
Answer:
Answer is (D) n
Step-by-step explanation:
Probability density function defines the likelihood of an outcome for a discrete random variable or a continuous random variable whose integral gives the probability that the value of the variable lies in the same interval.
The constant here is C
CX" implies CX prime prime (meaning that X has been differentiated twice).
The value of C is n, which is the number of values of X.
The mean arrival rate of flights at Philadelphia International Airport is 195 flights or less per hour with a historical standard deviation of 13 flights. To increase arrivals, a new air traffic control procedure is implemented. In the next 30 days, the arrival rate per day is given in the data vector below called flights. Air traffic control manager wants to test if there is sufficient evidence that arrival rate has increased.
flights <- c(210, 215, 200, 189, 200, 213, 202, 181, 197, 199,
193, 209, 215, 192, 179, 196, 225, 199, 196, 210,
199, 188, 174, 176, 202, 195, 195, 208, 222, 221)
a) Find sample mean and sample standard deviation of arrival rate using R functions mean() and sd().
b) Is this a left-tailed, right-tailed or two-tailed test? Formulate the null and alternative hypothesis.
c) What is the statistical decision at the significance level α = .01?
Answer:
a) The sample mean is M=200.
The sample standard deviation is s=13.19.
b) Right-tailed. The null and alternative hypothesis are:
[tex]H_0: \mu=195\\\\H_a:\mu> 195[/tex]
c) At a significance level of 0.01, there is notenough evidence to support the claim that the arrival rate is significantly higher than 195.
Step-by-step explanation:
We start by calculating the sample and standard deviation.
The sample size is n=30.
The sample mean is M=200.
The sample standard deviation is s=13.19.
[tex]M=\dfrac{1}{n}\sum_{i=1}^n\,x_i\\\\\\M=\dfrac{1}{30}(210+215+200+. . .+221)\\\\\\M=\dfrac{6000}{30}\\\\\\M=200\\\\\\s=\sqrt{\dfrac{1}{n-1}\sum_{i=1}^n\,(x_i-M)^2}\\\\\\s=\sqrt{\dfrac{1}{29}((210-200)^2+(215-200)^2+(200-200)^2+. . . +(221-200)^2)}\\\\\\s=\sqrt{\dfrac{5048}{29}}\\\\\\s=\sqrt{174.07}=13.19\\\\\\[/tex]
This is a hypothesis test for the population mean.
The claim is that the arrival rate is significantly higher than 195. As we are interested in only the higher tail for a significant effect, this is a right-tailed test.
Then, the null and alternative hypothesis are:
[tex]H_0: \mu=195\\\\H_a:\mu> 195[/tex]
The significance level is 0.01.
The standard deviation of the population is known and has a value of σ=13.
We can calculate the standard error as:
[tex]\sigma_M=\dfrac{\sigma}{\sqrt{n}}=\dfrac{13}{\sqrt{30}}=2.373[/tex]
Then, we can calculate the z-statistic as:
[tex]z=\dfrac{M-\mu}{\sigma_M}=\dfrac{200-195}{2.373}=\dfrac{5}{2.373}=2.107[/tex]
This test is a right-tailed test, so the P-value for this test is calculated as:
[tex]\text{P-value}=P(z>2.107)=0.018[/tex]
As the P-value (0.018) is bigger than the significance level (0.01), the effect is not significant.
The null hypothesis failed to be rejected.
At a significance level of 0.01, there is notenough evidence to support the claim that the arrival rate is significantly higher than 195.
1. Find the value of x
37.5
17
52.5
a. 39.5
b. 75
c. 40
d. 42.5
Answer:
d
Step-by-step explanation:
The segment inside the triangle bisects the angle and divides the opposite sides into segments that are proportional to the other two sides, that is
[tex]\frac{x}{17}[/tex] = [tex]\frac{37.5}{52.5-37.5}[/tex] = [tex]\frac{37.5}{15}[/tex] ( cross- multiply )
15x = 637.5 ( divide both sides by 15 )
x = 42.5 → d
By about how much will f (x comma y comma z )equalsln StartRoot x squared plus y squared plus z squared EndRoot change if the point Upper P (x comma y comma z )moves from Upper P 0 (6 comma 4 comma 12 )a distance of dsequals0.1 unit in the direction of 3 Bold i plus 6 Bold j minus 2 Bold k?
Answer:
pls format
Step-by-step explanation:
please answer someone
Answer:
answer C
Step-by-step explanation:
hello
set A is [tex]10^x[/tex]
set B is 1000+50(x-1)
so set A is an exponential function and the values increase at a faster rate than set B
hope this helps
Which is the graph of the equation v- 1 = (-3)?
Step-by-step explanation:
The equation is v-1 = -3
V-1 = -3 add one in both sides v -1 +1 = -3+1 v = -2Here is the graph :
7 + x - 15 = -2.67 solve for x
Answer:
5.33
Step-by-step explanation:
Move your numbers so that they're separate from the variables. You should now have x = -2.67 + 8; x = 5.33
Answer:
x=5.33
Step-by-step explanation:
7+x-15=-2.67
7-15+x=-2.67
Add 7 and -15
-8+x=-2.67
Add 8 on both sides
which equal to 5.33
x=5.33
solve the inequality:8x+3>2x-15
8x + 3 > 2x - 15
8x - 2x > -15 - 3
6x > -18
x > -3
Answer:
x > -3
Step-by-step explanation:
8x + 3 > 2x - 15
Add -3 and -2x on both sides.
8x - 2x > -15 - 3
6x > -18
Divide 6 into both sides.
x > -18/6
x > -3
Which could be the side lengths of a triangle? (A) 2,2,4 (B) 3,4,7 (C) 4,5,8 (D) 5,5,10 (E) 7,3,10 PLEASE HELP
Answer:
(C) 4,5,8
Step-by-step explanation:
Since 4+5 = 9 and 9 is bigger than 8, that means that the side 8 can fit into the triangle without there being an open space.
Answer:
Option C { 4,5,8 }
Step-by-step explanation:
By the Triangle Inequality Theorem, the length of two sides together must be greater than the length of the remaining side. Respectively their difference must be less than the length of the another side.
* I like to memorize this concept by thinking about a door. The more you open the door, the greater the distance between the door and the wall - as they are proportional. That is how we concluded this theorem.
______
{ 2, 2, 4 } is our first option. The difference of 4 and 2 is equal to the remaining length, 2. { 3, 4, 7 } is not applicable as well, considering that the addition of 3 and 4 is equivalent to the length of the 3rd side, 7. However, the lengths { 4, 5,8 } have no such " errors. " It could be the side lengths of a possible triangle.
______
Solution = { 4,5,8 }
1- if angle A = 30, then its complementary is -- and its supplementary is
2- If a triangle has an area of 360, and its base = 10, what is its height?
3- if two triangles have the same angle measures, then the triangles are
4. What is the definition of similar triangles?
5- One of triangle congruence tests is SSS, what are 3 other congruent tests
6- What is a regular polygon?
7- If a rectangle has an area of 240 and a length of 24, what is the width?
8- Colinear points lie on the same
9- 3 non-colinear points determine a
10- The sum of 2 supplementary angles add up to -------
1 - complementary = 90- 30 = 60
suplementary = 180- 30 = 150
2 - area = hb/2 = 360 = hb/2 = h = 72
3 - similar
4- see number 3
5 - asa, ssa, sas
6 - polygon that had all equal angle measures and sides (equiangular and equilateral)
7 - length x width = area so
240 / 24 = 10
8 - line
9 - triangle
10 - 180, as see in question 1
vote me brainliest ):>
Simplify.
35 - (42 + 5)
━━━━━━━☆☆━━━━━━━
▹ Answer
-12
▹ Step-by-Step Explanation
35 - (42 + 5)
35 - 47 = -12
Hope this helps!
- CloutAnswers ❁
Brainliest is greatly appreciated!
━━━━━━━☆☆━━━━━━━
Answer:
Hello!
~~~~~~~~~~~~~~~~~~~~~~~~~
35 - (42 + 5) =
-12
~~~~~~~~~~~~~~~~~~~~~~~~~
Step-by-step explanation: Simplify the expression.
Hope this helped you! Brainliest would be nice. ❤︎
A property is listed for $580,000. The listing agreement promises to
pay a 7% commission. A buyer makes an offer of $547,000 on May 4th
and gives a $2,000 deposit. The offer is accepted with no change on
May 8th and a closing date is set for June 5th. The day of closing goes
to the buyer. Taxes for the property are $5309 and are paid in arrears.
The buyer will pay for the inspection at closing $280.00 and the seller
will pay for a home warranty in the amount of $360.00. The mortgage
remaining is $480,000. Using the 365 day method, what will the seller
net?
$506,095
$544,386
$26,096
$26,085.00
Answer:
$26,096
Step-by-step explanation:
property taxes = 31 January + 28 February + 31 March + 30 April + 31 May + 4 June = 155 days
property taxes = (155 days/365 days) x $5,309 = $2,254
agent's commission = 7% x $547,000 = $38,290
seller's net = $547,000 - $480,000 (mortgage) - $38,290 (agent's commission) - $360 (home warranty) - $2,254 (property taxes) = $26,096
Answer:
26,096
Step-by-step explanation:
Proration using 365-day method:
Buyer days are June - December 210 days (June 30 + July 31 + August 31 + September 30 + October 31 + November 30 + December 31 - June 4 days)
Seller days are January - June 155 days (January 31 + February 28 + March 31 + April 30 + May 31 + June 30 - June 26 days)
Formula with closing day to buyer: 210/365 x $5,309 = $3,054.49 --> $5,309 - $3,054.49 = $2,254.51 property taxes
Commission:
$547,000 sale price x .07 commission fee = $38,290 commission
Seller Net:
$547,000 sale price - $480,000 mortgage = $67,000 - $38,290 commission = $28,710 - $360.00 home warranty = $28,350 - $2,254.51 = $26,096
Find the sum. Please
Answer:
[tex]\dfrac{2y^2 +12y -8}{y^3-3y+2}[/tex]
Step-by-step explanation:
It usually works to factor the denominators, so you can determine the least common denominator.
[tex]\dfrac{2y}{y^2-2y+1}+\dfrac{8}{y^2+y-2}=\dfrac{2y}{(y-1)^2}+\dfrac{8}{(y-1)(y+2)}\\\\=\dfrac{2y(y+2)}{(y-1)^2(y+2)}+\dfrac{8(y-1)}{(y-1)^2(y+2)}=\dfrac{2y^2+4y+8y-8}{(y-1)^2(y+2)}\\\\=\boxed{\dfrac{2y^2 +12y -8}{y^3-3y+2}}[/tex]
6th grade math , please help
Answer: 4 to 10 then it’s 6 to 20 then it’s 8 to 25 Then it’s 10 to 30 then it’s 12 to 35 I hope this is the answer
Step-by-step explanation:
Step-by-step explanation:
Ava is walking at a constant rate of 5 feet each 2s so :
5 ft ⇒ 2 sWe should keep adding 2s in the time and 5 feet in the distance
Let's complete the chart:
0⇒02⇒54⇒106⇒158⇒2010⇒25I travelled at 60km/h and took 2 hours for a certain journey. How long would it have taken me if I had travelled at 50km/h?
Answer:
2 hours and 24 minutes
Step-by-step explanation:
2 hours at 60 km/h means you have travelled 2*60=120 km
120 km at 50 km/h takes 120/50 = 2.4 hours
2.4 hours is 2 hours and 0.4*60 = 24 minutes.
Please help me
And explain
Answer: 144
Step-by-step explanation:
ABD plus DBC makes up ABC so when you add the two it will give you a whole (76+68).
CAN SOMEONE PLEASE HELP ME THIS IS DUE SOON!!
Answer:
95 ft²
Step-by-step explanation:
Given:
regular pyramid with,
Square base of side length (s) = 5 ft
Slant height (l) = 7 ft
Required:
Surface area
Solution:
Surface area of a regular pyramid = ½*P*l + B
Where,
P = perimeter of the square base = 4(s) = 4(5) = 20 ft
l = slant height = 7 ft
B = area of base = s² = 5² = 25 ft²
Surface area = ½*20*7 + 25
= 10*7 + 25
= 70 + 25
Surface area of regular pyramid = 95 ft²
Which is the first step in simplifying 4(3x-2)+6x(2-1)
Answer:
4(3x-2)+6x(2x-1)
12x-8+12^2x-6x
12x-6x +12^2x-8
6x+12^2x-8
Answer:
the first step in simplifying 4(3x-2)+6x(2-1) is to do subtract 1 from 2 in the second set of parenthesis. That will get you 4(3x-2)+6x(1)
The equation completely simplified is 18x-8
-look in the step-by-step explanation if you want to know all the steps to simplifyinh the equation
Step-by-step explanation:
Now if you want to know the rest here it is:
Then use the Distributive Property:
-distribute the 4 into (3x-2) to get 12x-8
-then distribut the 6x into (1) to get 6x
Your equation is now 12x-8+6x
Finally, add 12x and 6x to simplify the equation as much as you can
you get 18x-8 as you final, most simplified answer
Jenna worked 13 hours more than Jose last month. If Jenna worked 9 hours for every 4 hours that Jose worked, how many hours did they each work?