Birth weights of babies in the United States can be modeled by a normal distribution with mean of 7.17 pounds and standard deviation 1.21 pounds. Those weighing less than 5.51 pounds are considered to be of low birth weight. What is the probability that a randomly selected baby in the United States will be of low birth weight?

1 answer

You can play around with Z table stuff at

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