The height of 700 students is normally distributed with mean 63cm. And standard deviation 4 cm.if students are selected at random then find how many students height less than 69 cm
Z = (score-mean)/SD = (69-63) SEm
SEm = SD/√n
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability. Multiply by 700.