A study has shown that among people without any preschool education, 32% were employed at age 19. If 100 people without preschool education are selected, find the probability that 40 or fewer are employed.

Answer 1

Find z.

z = (x - mean)sd

mean = np
sd = √npq

n = 100
p = .32
q = 1 - p = .68

Substitute 40 for x in the formula. Calculate mean and standard deviation. Plug in the other values. Find z, then check z-table for your probability.

I hope this will help get you started.