In: Statistics and Probability
A) According to the National Institute of Health, 34% of adults in the United States are overweight. Suppose we sample 20 adults. Let X denote the number of overweight people among them.
What is the probability that more than 6 of the adults will be overweight? Round to four decimal places.
B) According to the National Institute of Health, 34% of adults in the United States are overweight. Suppose we sample 20 adults. Let X denote the number of overweight people among them.
What is the probability that exactly 5 of the adults will be overweight? Round to four decimal places.
C) The weight of infants at a New York hospital has a mean of 7.5 pounds and a standard deviation of 0.95 pounds. Weights are approximately normally distributed.
What is the probability that a randomly selected infant will have a weight between 6.8 pounds and 7.9 pounds? Round to four decimal places.
D) The lengths of pregnancies are normally distributed with a mean of 248 days and a standard deviation of 15 days. If a pregnant woman is randomly selected, what is the probability that her pregnancy lasts more than 275 days? Round to four decimal places.