A manufacturer of LED light bulbs knows that 3% of the production of their 15W bulbs will be defective.

Question

What is the probability that exactly 5 bulbs in a carton of 144 bulbs will be defective?

Answer 1

Each light bulb is independent of other light bulbs so can use binomial distribution formula to compute probability.

5 139

P(5 defectives in 144 tries) = 144! (0.03) (0.97)

-------

5! 139!