Represent the following sentence as an algebraic expression, where "a number" is the letter x. The product of 8 and a number.

Suppose you can somehow choose two people at random who took the SAT in 2014. A reminder that scores were Normally distributed w

Sindrei [870]

Answer:

22.29% probability that both of them scored above a 1520

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

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 problem, we have that:

$\mu = 1497, \sigma = 322$

The first step to solve the question is find the probability that a student has of scoring above 1520, which is 1 subtracted by the pvalue of Z when X = 1520.

So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{1520 - 1497}{322}$

$Z = 0.07$

$Z = 0.07$ has a pvalue of 0.5279

1 - 0.5279 = 0.4721

Each students has a 0.4721 probability of scoring above 1520.

What is the probability that both of them scored above a 1520?

Each students has a 0.4721 probability of scoring above 1520. So

$P = 0.4721*0.4721 = 0.2229$

22.29% probability that both of them scored above a 1520

8 0

2 years ago

Last year, James earned £1,100 per month. This year, he's had a 4% increase in his monthly pay. He worked 40 hours per week for

avanturin [10]

Answer:

A = £7.15 per hour

James' average pay per hour this year is £7.15 per hour

Step-by-step explanation:

Given;

Last year pay = £1,100 per month

This year, he's had a 4% increase in his monthly pay

This year pay P = 1,100 + 4% of 1,100 = 1,100 +1,100(0.04)

This year pay P = £1,144 per month

Yearly pay Tp= 12 × P = 12 × £1,144 = £13,728

Number of hours worked this year;

He worked 40 hours per week for 48 weeks in the year

N = 40 hours per week × 48 weeks per year

N = 1920 hours per year

Average pay per hour this year A;

A = Yearly pay/Number of hours worked this year

A = Tp/N

A = £13,728/1920hours

A = £7.15 per hour

James' average pay per hour this year is £7.15 per hour

5 0

2 years ago

Please help!!!!!

Naya [18.7K]

Your answer is 80. A triangle’s angles add up to 180 degrees. Therefore, you need to subtract 30 and 70 from 180 to find your answer: 180-(30+70)=80 or 180-70-30=80

5 0

3 years ago

Someone help please. A sports website writing team tries to predict the number of visits to their site based on the number of po

dimaraw [331]

Answer:

The scatter plot shows a positive correlation because the number of website visit increases as the number of posts increases

Step-by-step explanation:

The scatter plot shows a positive correlation because the number of website visit increases as the number of posts increases

6 0

2 years ago

Calculat the length of the circumference of a circle with diameter of 8cm.

mr_godi [17]

Hello there!

The formula for finding the circumference of a circle is 2 $\pi$ r (or 2*3*r in your terms). Although we don't have the radius yet, we can certainly find it pretty easily. Keep in mind that the radius will always be half the diameter. So, let's find the radius.

8 / 2 = 4; now we have everything we need to solve for the circumference.

2*3*4 is our expression. Now let's simplify it.
2 * 3 = 6
6 * 4 = 24

Your circumference is 24cm.

I hope this helps!

7 0

2 years ago

Represent the following sentence as an algebraic expression, where "a number" is the letter x. The product of 8 and a number.​

Represent the following sentence as an algebraic expression, where "a number" is the letter x. The product of 8 and a number.