Question

Consider the number of days that it takes to take the Christmas tree down after Christmas.

Suppose that it is taken down an average of 9.5 days after Christmas with standard deviation of 3.1 and that

this is normally distributed?

(a) What is the probability of a tree being taken down in eight or fewer days?

(b) What is the probability of a tree being taken down in exactly eight days? Would you think your

answer would change if you instead modeled this probability as being discrete?

(c) What is the probability of a tree being taken down ten or more days later?

(d) What is the probability of a tree being taken down between eight and eighteen days after Christ-

mas?

(e) Twenty- five percent of trees are taken down before x days. What is x?

Answer 1