Question

In the past, Ben has been able to hit a baseball at the batting cage 20% of the time. He decides to head back to the batting cage. (a) What is the probability that his first hit will be on the eighth pitch? (b) What is the probability that his first hit will not be within the first nine pitches? *

Answer 1

Answer: (4/5)^7 x 1/5

Step-by-step explanation: This is a geometric probability distribution. The probability of a success is 20% = 1/5 and the probability of a failure is therefore 4/5.

We want to know the probability that Ben is successful on the eight attempt. This means he has failed the first 7 times but succeeds on the 8th try.

So probability is (4/5)^7 x 1/5