I really don't understand this:

Question

The average height of a sixth grade class is 64 and a standard deviation of 2. What is a student's z-score if his height is 66?

Answer 1

The formula for the z-score is (Value - Mean)/Std. Deviation, or z = (x - µ)/σ.

The z score represents the number of standard deviations that the value x is from the mean μ.

The average (mean) is 64 and the standard deviation is 2. The value is 66.

So z = (66 - 64)/2.

Just calculate!

Answer 2

Z-score basically means the number of standard deviations an observed value is from the mean in a normal distribution. In this case, the average/mean is 64, and our observed value is 66. Because our standard deviation is 2, we can calculate z = (66-64)/2 = 2/2 = 1, which tells us that 66 is one standard deviation away from 64. This means the z-score of the student with a height of 66 is 1.

Hope this helped! Let me know if I need to clarify anything else.