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

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.

Answer 2

Answer:

-.4

Step-by-step 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