The number of lightning strikes on a square kilometer of ope

The number of lightning strikes on a square kilometer of open ground in a year has mean 5.6 and standard deviation 1.6. (These values are typical of much of the United States.) The National Lightning Detection Network uses automatic sensors to watch for lightning in a sample of 40 randomly chosen square kilometers. (a) What are the mean and standard deviation of X, the mean number of strikes per square kilometer?

(b) What is the probability that X is 5.3 or less? (Use 3 decimal places)

Solution