Question

9. Assume the weight, W, of a randomly selected adult has a normal distribution with a mean
of 175 pounds and a standard deviation of 10 pounds.. Find the probability, P(W < 190), that
a randomly selected adult weighs less than 190 pounds.

Answer 1

http://davidmlane.com/hyperstat/z_table.html

Answer 2

Another method.

Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion related to the Z score.