Question

Suppose that the probability that your mail is delivered before 2 pm is .90. What is the probability that your mail will be delivered before 2pm for two consecutive days? Give your answer as a decimal.

Answer 1

Given that the probability of mail being delivered is 0.90, to evaluate the probability that the mail will be delivered before 2 p.m for 2 consecutive days will be evaluated as follows:
Let the probability that the milk will be delivered before 2 p.m be P(x). Since the two days are independent events, the probability of the mail being delivered before 2 p.m in 2 consecutive days will be:
P(x)×P(x)
=0.9×0.9
=0.81