Question

Given a mean of 43.8 and a standard deviation of 8.7, what is the z-score of the value 40 rounded to the nearest tenth?

Answer 1

-.4

Explanation:

z score = value-mean / standard deviation

z score = 40-43.8 / 8.7

-.436 = 40-43.8 / 8.7

-.436 to nearest 10th -.4

Answer 2

For the answer to the question above,
Sample mean is given by,

x = (1/n)∑x˅i .... ˅ means sub

x = (1/5)(60 + 40 + 35 + 45 + 39)
= 43.8

z-score is given by,

z = (X - μ)/σ .... μ is population mean, σ is the standard deviation

z = (43.8 - 43.8)/8.7
= 0
so the answer is zero
I hope my answer helped you.