Question

Suppose that you are looking for a student at your college who lives within five miles ofyou. You know that 55 percent of the 25,000 students do live within five miles of you. Yourandomly contact students from the college until one says he or she lives within five miles ofyou. What is the probability that you need to contact four people

Answer 1

The probability that I need to contact four people is 9.11%.

Explanation:

Since I am looking for a student at my college who lives within five miles of me, and I know that 55 percent of the 25,000 students do live within five miles of me, and I randomly contact students from the college until one says he or she lives within five miles of me, to determine what is the probability that I need to contact four people, the following calculation must be performed:

0.45 x 0.45 x 0.45 = X

0.2025 x 0.45 = X

0.091125 = X

Therefore, the probability that I need to contact four people is 9.11%.