Question

A shipment of 8 computers contains 3 with defects. Find the probability that a sample of size 2, drawn from the 8, will not contain a defective computer.

What is the probability that a sample of 2 of the 8 computers will not contain a defective computer?
(Type an integer or a simplified fraction.)

Answer 1

5/28

Explanation:

First of all, probability is defined as the number of ways a certain event can happen divided by the total ways of an event happening. In this scenario, we are asked to find the number of non-defective computers divided by the total ways that a sample of two can be chosen.

The number of ways to choose 2 computers from 8 can be written as
`8\choose2`, which is equal to
`(8\cdot7)/(2)`, which is 28. Now, there are 3 defective computers, for a total of 5 non-defective computers, so the probability is 5/28.