Answer: B & C
Step-by-step explanation:
Putting the values of x & y in all 4 equations we see that the values satisfy equations B & C only. Hence B & C are correct answers
Write the fraction in simplest form. (3/6) x (7/10)
Scores on the SAT test have a mean of 1518 and a standard deviation of 325. Scores on the ACT test have a mean of 21.1 and a standard deviation of 4.8. Which of the following choices is not true?
A. The ACT score gt 17.0 is relatively better than the SAT score of 1490 a relatively better then the SAT score of 1490 .
B. An SAT score of 1490 has a z-score of -0.09
C. The SAT score of 1490 is relatively better than the ACT score of 17.0.
Answer:
The ACT score gt 17.0 is relatively better than the SAT score of 1490 a relatively better then the SAT score of 1490 .
Step-by-step explanation:
Z-score:
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
A. The ACT score gt 17.0 is relatively better than the SAT score of 1490 a relatively better then the SAT score of 1490.
We find the z-score for each of these options. Whichever has the higher z-score is the better grade.
ACT:
Mean 21.1, standard deviation of 4.8. Score of 17. So [tex]\mu = 21.1, \sigma = 4.8, X = 17[/tex]
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{17 - 21.1}{4.8}[/tex]
[tex]Z = -0.85[/tex]
SAT:
Scores on the SAT test have a mean of 1518 and a standard deviation of 325. Score of 1490. So [tex]\mu = 1518, \sigma = 325, X = 1490[/tex]
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{1490 - 1518}{325}[/tex]
[tex]Z = -0.09[/tex]
The SAT score of 1490 has the higher z-score, so this is the better score, which means that this statement is false and A. is the answer of this question.
B. An SAT score of 1490 has a z-score of -0.09
From A., this is true
C. The SAT score of 1490 is relatively better than the ACT score of 17.0.
From A., this is true.
what are the multiples of 5,6,8,9?
cos3x-3cosx=cos2x+1 {Domain: 0<=x<=360} The solution is 90deg, 180deg, and 270deg, but what are the simplifying steps in between? I know all trig identities.
Step-by-step explanation:
cos(3x) − 3 cos x = cos(2x) + 1
Use triple and double angle formulas.
(4 cos³x − 3 cos x) − 3 cos x = (2 cos²x − 1) + 1
Simplify.
4 cos³x − 6 cos x = 2 cos²x
4 cos³x − 2 cos²x − 6 cos x = 0
2 cos³x − cos²x − 3 cos x = 0
Factor.
cos x (2 cos²x − cos x − 3) = 0
cos x (cos x + 1) (2 cos x − 3) = 0
Solve.
cos x = 0 → x = 90°, 270°
cos x + 1 = 0 → x = 180°
2 cos x − 3 = 0 → no solution
A poll found that 5% of teenagers (ages 13 to 17) suffer from arachnophobia and are extremely afraid of spiders. At a summer camp there are 11 teenagers sleeping in each tent. Assume that these 11 teenagers are independent of each other. (Round your answers to four decimal places.)
a) Calculate the probability that at least one of them suffers from arachnophobia. - 0.4312
b) Calculate the probability that exactly 2 of them suffer from arachnophobia? 0.08666
c) Calculate the probability that at most 1 of them suffers from arachnophobia? What is C?
Answer:
a) Calculate the probability that at least one of them suffers from arachnophobia.
x = number of students suffering from arachnophobia
= P(x ≥ 1)
= 1 - P(x = 0)
= 1 - [0.05⁰ x (1 - 0.05)¹¹⁻⁰ ]
= 1 - (0.95)¹¹
= 0.4311999 = 0.4312
b) Calculate the probability that exactly 2 of them suffer from arachnophobia? 0.08666
= P(x = 2)
= (¹¹₂) x (0.05)² x (0.95)⁹
where ¹¹₂ = 11! / (2!9!) = (11 x 10) / (2 x 1) = 55
= 55 x 0.0025 x 0.630249409 = 0.086659293 = 0.0867
c) Calculate the probability that at most 1 of them suffers from arachnophobia?
P(x ≤ 1)
= P(x = 0) + P(x = 1)
= [(¹¹₀) x 0.05⁰ x 0.95¹¹] + [(¹¹₁) x 0.05¹ x 0.95¹⁰]
= (1 x 1 x 0.5688) + (11 x 0.05 x 0.598736939) = 0.5688 + 0.3293 = 0.8981
1. A fruitseller bought 200 apples for Rs 300.40 of them were rotten and thrown away.
She sold the rest at Rs 2.25 each. Find its gain or loss percent.
253
A Book of Mathematics-8
Answer:
ok I am tellin6 to you
Step-by-step explanation:
ok I will tell to you
The scheduled arrival time for a daily flight from Boston to New York is 9:30 am. Historical data show that the arrival time follows the continuous uniform distribution with an early arrival time of 9:07 am and a late arrival time of 9:57 am.a. After converting the time data to a minute scale, calculate the mean and the standard deviation for the distribution. (Round your answers to 2 decimal places.)Mean:____________________________ minutes Standard deviation: _________________ minutes b. What is the probability that a flight arrives late (later than 9:30 am)? (Do not round intermediate calculations. Round your answer to 2 decimal places.)Probability:________
Answer:
Step-by-step explanation:
Let x be a random variable representing the flight arrival time from Boston to New York.
For a uniform probability distribution, the notation is
X U(a, b) where a is the lowest value of x and b is the lowest value of x
The probability density function, f(x) = 1/(b - a)
Mean, µ = (a + b)/2
Standard deviation, σ = √(b - a)²/12
From the information given, the time difference in minutes is 9:57 - 9:07 = 50 minutes. Therefore,
a = 0
b = 50
µ = (0 + 50)/2 = 25
σ = √(50 - 0)²/12 = 14.43
b) converting to minutes, it is 9:30 - 9:07 = 23 minutes
the probability that a flight arrives late(later than 9:30 am) is expressed as P(x > 23)
f(x) = 1/(50) = 0.02
P(x > 23) = (50 - 23)0.02 = 0.54
Find the percent of increase. Original Price: $135 Retail Price: $162
20%
Here's a tip: Always start percentage calculating with dividing the current number by 10.
Please answer this correctly
Answer:
The first answer.
Step-by-step explanation:
The first answer.
What was the temperature of the air?
'was 2C warmer than the surface of the ice'
warmer than= +2c
Temp. of ice=-2c
-2c+2c=0
Answer:
Option 1
Step-by-step explanation:
The temp. was -2 degrees celsius.
The temp. got 2 degrees celsius warmer.
-2 + 2 = 0
What are the y-intercepts for each function? What do these y-intercepts represent?
Answer:
In a function that is represented by Y=mx+b b would be the y-intercept
Definition of y-intercept. : the y-coordinate of a point where a line, curve, or surface intersects the y-axis.
A political candidate has asked you to conduct a poll to determine what percentage of people support her. If the candidate only wants a 4% margin of error at a 99% confidence level, what size of sample is needed? Give your answer in whole people.
Answer:
Step-by-step explanation:
Hello!
The variable of interest is:
X: Number of people that support the candidate.
You need to calculate the sample size to estimate the population proportion of supporters given a confidence level of 99% and a margin of error of 4%
The margin of error of the confidence level for the population proportion is
d= [tex]Z_{1-\alpha /2}[/tex] * [tex]\sqrt{\frac{p'(1-p')}{n} }[/tex]
From this formula you have to clear the value of n:
[tex]\frac{d}{Z_{1-\alpha /2}}[/tex]= [tex]\sqrt{\frac{p'(1-p')}{n} }[/tex]
[tex](\frac{d}{Z_{1-\alpha /2}})^2[/tex]= [tex]\frac{p'(1-p')}{n}[/tex]
[tex]n*(\frac{d}{Z_{1-\alpha /2}})^2[/tex]= [tex]p'(1-p')[/tex]
n= [tex]p'(1-p') * (\frac{Z_{1-\alpha/2}}{d} )^2[/tex]
[tex]Z_{1-\alpha/2}= Z_{0.995}= 2.586[/tex]
sample proportion "p'" since there is no sample information, nor any previous information is known, you have to consider it as the "worse case scenario" and use the value of p'= 0.50
d= 0.04
[tex]n= p'(1-p') * (\frac{Z_{1-\alpha/2}}{d} )^2= 0.5*0.5*(\frac{2.586}{0.04} )^2= 1044.9= 1045[/tex]
She has to take a sample of 1045 people to estimate the population proportion of her supporters with a confidence level of 99% and a margin of error of 4%
I hope this helps!
Please answer this correctly
Answer:
Option 2
Step-by-step explanation:
The average temperature in January is -1 degrees celsius. Last year, it was 1 degrees celsius higher than the average.
-1 + 1 = 0
Answer:
The second answer.
Step-by-step explanation:
The average temp. is -1C.
'was 1C warmer' = +1
-1+1=0
Alexis and Jessica are shopping. Alexis buys 4 pairs of pants and 3 necklaces and pays $216. Jessica buys 7 pairs of pants and 2 necklaces and pays $300. Solve for the price of each item. Each pair of pants costs _____ dollars Each necklace costs________ dollars
Step-by-step explanation:
let us keep the price of pants as x
and price of necklace as y
Simultaneous equations comes as follows:
4x + 3y = 216 for Alexis
7x + 2y = 300 for Jess
we'll make either x or y equal
here let's make y equal
2 ( 4x + 3y = 216)
3 ( 7x + 2y = 300)
8x + 6y = 432
21x + 6y = 900
21x - 8x = 900 - 432
13x = 468
x = $36
so a pant costs $36
And
3y = 72
y = $ 24
so a necklace costs $36
by which number -7 /25 should be divided to get -1/15?
Answer:
21/5
Step-by-step explanation:
if a/b = c, then b=a/c
in other words:
divide -7/25 by -1/15 to get the answer
It also helps to use the fact that a/b / c/d = a/b * d/c
-7/25 / -1/15 = -7/25 * -15/1
= 105 / 25
= 21 / 5
Answer:
[tex]4 \frac{1}{5} [/tex]
Step-by-step explanation:
[tex] \frac{ - 7}{25} \div x = \frac{ - 1}{15} [/tex]
[tex]x = \frac{ - 7}{25} \div \frac{ - 1}{15} [/tex]
[tex] = \frac{7}{25} \times \frac{15}{1} [/tex]
[tex] = \frac{21}{5} = 4 \frac{1}{5} [/tex]
Find an equation of the tangent line to the curve at the given point.
y = √ (x) , (16, 4)
Answer: y=1/8*x+2
Step-by-step explanation:
The equation of any tangent line is y=a*x+b (1)
To the equation of the tangent line we have to find the coefficients a and b and the to substitute them to equation (1).
As we know a=y'(x0) ( where x0=16)
So y'(x)= (√ (x) )' = 1/(2*√x)
a=y'(x0)= 1/(2*√16)=1/(2*4)=1/8
So lets substitute a in equation (1):
y=1/8 *x+b
Now we have to find b
We know that the point (16, 4) belongs to the tangent line.
That means
4=1/8*16+b => 4=2+b => b=2
SO the equation of the tangent line is y=1/8*x+2
Find the product of: 1.(6a²+2b³) and -4ab²
Answer:
[tex]-24a^3b^2 -8ab^5\\[/tex]
Step-by-step explanation:
Given the two expression (6a²+2b³) and -4ab², to find their product, the following steps are valid;
[tex]= (6a^2+2b^3) *-4ab^2\\= (6a^2+2b^3)(-4ab^2)\\= (6a^2)(-4ab^2)+(2b^3)(-4ab^2) \\= -24a^3b^2 + (-8ab^5)\\= -24a^3b^2 -8ab^5\\[/tex]
The final expression gives the required product
Please help need to do corrections and can't figure out this homework question??
Don glover borrowed $14,000 for 250 days and paid $806.20 in simple interest on the loan. what annual simple interest rate did don pay on the loan?
Simple interest formula = I = PRT where I = interest, P = principal, r = interest rate and t = time.
i = 806.20, p = 14,000 t = 250 days.
Change t to be fraction of a full year: t = 250/365
Now solve for r:
806.20 = 14000 x r x 250/365
Simplify :
806.20 = r x 9589.04
Divide both sides by 9589.04:
r = 806.20 / 9589.04
r = 0.08407
Multiply by 100 to get percent:
r = 8.41% (rounded to nearest hundredth)
Check that your solutions to part (a) and (b) are consistent by substituting the expression for y into your solution for part (a).
9x^2 - y^2 = 1
Answer:
Step-by-step explanation:
The question is incomplete. Find the complete question in the attached file.
a) Given the expression 9x^2 - y^2 = 1
Differentiating implicitly will give;
[tex]18x-2y\frac{dy}{dx} = 0\\[/tex]
We can then make dy/dx the subject of the formula as shown;
[tex]18x = 2y\frac{dy}{dx}\\\frac{dy}{dx} = \frac{18x}{2y} \\\frac{dy}{dx} = \frac{9x}{y} \\y' = \frac{9x}{y}[/tex]
b) In order to solve the question explicitly, we will first have to make x the subject of the formula before differentiating.
[tex]9x^{2} -y^{2} = 1\\9x^{2} = 1+ y^{2}\\y^{2} =9x^{2}- 1\\y^{2} = 9x^{2} - 1\\y = \sqrt{9x^{2}- 1 } \\[/tex]
Using chain rule to solve the equation;
let;
[tex]u = 9x^{2} -1\\ y = u^{1/2}[/tex]
du/dx = 18x
dy/du = [tex]1/2u^{-1/2}[/tex]
dy/dx = dy/du * du/dx
dy/dx = [tex]1/2u^{-1/2} * 18x[/tex]
[tex]\frac{dy}{dx} = \frac{1}{2}({9x^{2}-1 } )^{-1/2} * 18x\\\frac{dy}{dx} = 9x({9x^{2} -1 } )^{-1/2} \\\frac{dy}{dx} = 9 x(\sqrt{{\frac{1}{9x^{2} -1} } }) \\\frac{dy}{dx} = \frac{9x}{\sqrt{9x^{2}-1 } }[/tex]
c) In order to confrim that solutions to part (a) and (b) are consistent, we will substitute [tex]y = \sqrt{9x^{2} - 1 } \\[/tex] into the answer in (a) as shown;
From (a) [tex]\frac{dy}{dx} = \frac{9x}{y} \\[/tex]
[tex]y' = \frac{9x}{ \sqrt{9x^{2} - 1 } \\} } \\}[/tex]
This shows that they are consistent
Is the area of this shape approximately 57 6 cm ? If not, give the correct area.
O True
O False
Answer: True
Step-by-step explanation: Taking the triangle from the left and moving it to the right creates a rectangle. From there just do 12.8×4.5.
Can somebody help me with a math problem?
Answer:
45°
Step-by-step explanation:
It is useful to have some idea what angles of different measures look like. The attachment may help you match the angle to an appropriate measure.
To me, it looks like a 45° angle.
__
Of course, you can always use a protractor and measure it. Make sure your screen or printer does not distort the image. (Printable versions of protractors are available on-line.)
What multiplication expression is equal to 3/5÷1/4 out of 3/5×1/4 or 5/3×1/4 or 3/5×1/4 or 3/5×4/1
Answer:
it would be 3/5*4/1
Step-by-step explanation:
To divide you multiply the first number by the reciprocal of the second number. Check and you'll see that the answer is the same. Hope this helps!
Answer:
The answer is 3/5 x 4/1
Step-by-step explanation:
what is the answer pls help me
Answer:
D.
Step-by-step explanation:
It is D. because there are lines on top of the letters meaning that the points PQ, QR, and PR are lines/sides.
You chose the answer already!
What methods does the textbook present for solving recurrences by guessing a bound and using mathematical induction to prove accuracy
Answer:
The correct answer is - Substitution method
Step-by-step explanation:
substitution method or strategy where an individual solve for one variable first and afterward substitute that articulation into the other equation. The significant thing here is that you are consistently substituting values that are the same.
Steps :
- Comprehend or solve one of the variables and make an equation.
- Substitute (module) this articulation into the other equation and comprehend.
- Resubstitute the value into the first equation to find the value of other variable.
100
x
x
||
=
8X10
15
||
Answer:
the answer is 6x
Step-by-step explanation:
What pages will be favored for the given search? Search terms: Michael OR Jordan A. Pages about Michael Jordan B. Pages about Michael, plus pages about OR, plus pages about Jordan C. Pages about Michael, plus pages about Jordan D. Pages about Michael, plus pages about Jordan, plus pages about both
Answer:
A. Pages about Michael Jordan.
Step-by-step explanation:
Michael Jordan, MJ, is a great basketball player, and has achieved one the best records in his career. He is a National Basketball Association (NBA) player with great skills and energy.
From the search item, the two names Michael OR Jordan is for one person, Michael Jordan. The search would combine the two names because it is a well known one and give an output on Michael Jordan. Thus, the pages that would be favored are pages about Michael Jordan.
How do you write 0.00609 in scientific notation? ____× 10^_____
Answer:
6.09 * 10 ^-3
Step-by-step explanation:
We want one non zero digit to the left of the decimal
Move the decimal 3 places to the right
6.09
The exponent is 3 and it is negative since we move to the right
6.09 * 10 ^-3
Answer:
6.09(10⁻³)
Step-by-step explanation:
Step 1: Put number into proper scientific decimal form
6.09
Step 2: Figure out how many decimals places it moves
Since it moves to the left 3, our exponent would be -3
On a normally distributed anxiety test with mean 48 and standard deviation 4, approximately what anxiety test score would put someone in the top 5 percent? Group of answer choices
Answer:
Anxiety score close to 54.58.
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question:
[tex]\mu = 48, \sigma = 4[/tex]
Approximately what anxiety test score would put someone in the top 5 percent?
We have to find the 100 - 5 = 95th percentile, which is X when Z has a pvalue of 0.95. So X when Z = 1.645.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]1.645 = \frac{X - 48}{4}[/tex]
[tex]X - 48 = 1.645*4[/tex]
[tex]X = 54.58[/tex]
Anxiety score close to 54.58.
In the diagram below, if AD= 100 and AC = 34, find CD.
A 59
B 76
C 45
D 66
Answer:
D. 66
Step-by-step explanation:
Well if AD is 100 and AC is 34 that leaves CD so we can just subtraction 34 from 100 and get 66.
Answer:
D. 66
Step-by-step explanation:
AD = 100
AC = 34
The whole line is 100. A part of the line is 34. The other part will be 66.
100 - 34 = 66
Question 1
You can ride a taxi and pay a flat rate of $25 to go anywhere in the city, or you can pay a
base rate of $15 and $1 per mile. For which trip would it make more sense to pay the base
rate and 1$ per mile?
15 mile trip
9 mile trip
25 mile trip
O 12 mile trip
Answer:
9 mile trip
Step-by-step explanation:
$15 + $15 = $30
$15 + $9 = $24
$15 + $25 = $40
$15 + $12 = $27
$30 > $25
$24 < $25
$40 > $25
$27 > $25