Anormal distribution of data has a mean of 90 and a standard deviation of 18. what is the approximate z-score for the value 64?

answer: it is -1.4! just took test

when x is value (64)

u is mean (90)

and sd is satandard deviation (18)

so z = 64 - 90 / 18

z = -26 / 18 = -1.44

answer:

z = \frac{x - u}{sd}

when x is value (64)

u is mean (90)

and sd is satandard deviation (18)

so z = 64 - 90 / 18

z = -26 / 18 = -1.44

step-by-step explanation: