Find the z value for x=40 for a normal distribution with μ=30 and σ=5.

Question

What does z=

Answer 1

Z = x-µ

     ------

        σ

 

z = (40-30)/5 = 10/5 = 2

Answer 2

z = (x-μ)/σ

 

   = (40-30)/5 = 2

 

This means that 40 lies 2 standard deviations above the mean.