Given that Jack's score on a test with a mean of 10 and standard deviation of 2 is 15, what is his z-score on the test?
A) -2.5
B) 2.5
C) -3
D) 3

Question

Quizplus · Accepted Answer

To find the z-score, we use the formula: 
z = (x - μ) / σ 
where x is the score, μ is the mean, and σ is the standard deviation.

In this case, 
x = 15 
μ = 10 
σ = 2

Plugging these values into the formula, we get: 
z = (15 - 10) / 2 = 2.5

Therefore, the answer is choice B.

Given That Jack's Score on a Test with a Mean