Assume that the ages for first marriages are normally distributed with a mean of 26 years and a standard deviation of 4 years. What is the probability that a person getting married for the first time is in his or her twenties

Suppose a team of pedestrians takes a simple random sample of 100 babies. in this sample, the babies have a head circumference of 46.35 cm and a standard deviation of 1.1 cm. what percent of the time would a random sample of 100 babies a sample mean that is not in the 90% confidence interval? a) 0% b)2.5% c)5% d)10%