Question

The College Board states that the average math SAT score is 514 with a standard deviation of 117. Colleen gathered data from 50 students in her graduating class and found the average score to be 529. She thinks that her class’s math SAT score is different from the average. Which of the following shows the correct z-statistic for this situation?
A. 0.38
B. 0.91
C. 1.26
D. 5.26

Answer 1

Answer:

B. 0.91

Step-by-step explanation:

The College Board states that the average math SAT score is 514 with a standard deviation of 117. Colleen gathered data from 50 students in her graduating class.

She found the average score to be 529.

We know that,

$z=\dfrac{x-\mu}{\frac{\sigma}{\sqrt{n}}}$

Here,

x = 529,

μ = 514,

σ = 117,

n = 50,

Putting the values,

$z=\dfrac{529-514}{\frac{117}{\sqrt{50}}}=0.91$

Answer 2

The solution would be like this for this specific problem:

Mean 1: 529
Mean 2: 514
ST: 117

529 - 514 = 15
15 / 117 = .13

I hope this helps and if you have any further questions, please don’t hesitate to ask again.