Question

A sample of 4 different calculators is randomly selected from a group containing 25 that are defective and 39 that have no defects. What is the probability that at least one of the calculators is defective?

Answer 1

Explanation:

You have a bunch of calculators: 25 are broken, and 39 work fine.

You want to know the chance that if you pick four calculators randomly, at least one of them is broken.

To do this, you first figure out the chance that none of the four calculators are broken. Then, you subtract that from 1 (which means 100%) to find the chance that at least one is broken.

So, the chance that none of the four calculators are broken is about 32.6%.

Now, to find the chance that at least one is broken, you subtract that from 100%, which gives you about 67.4%.

So, there's a 67.4% chance that at least one of the calculators you pick is broken.