Statistics Question

Baby weights: According to a recent National Health Statistics Reports, the weight of male babies less than 2 months old in the United States is normally distributed with mean 11.5 pounds and standard deviation 2.7 pounds.

  • What proportion of babies weigh between 10 and 14 pounds?
  • Is it unusual for a baby to weigh more than 17 pounds?

SAT scores: The College Board reports that in a recent year, the mean mathematics SAT score was 514, and the standard deviation was 118. A sample of 65 scores is chosen.

  • What is the probability that the sample mean score is less than 500?