In a manufacturing plant that produces new computers, a 0.15 probability exists that a computer will be defective. If five computers are manufactured, what’s the probability that all of them will be defective?

Question

anonymous · Answer

The chance that one is defective is 0.15
The chance that two are defective is 0.15 x 0.15, since each of the computers has the same chance of being defective on its own.
So for 5 computers, the chance that all 5 are defective is just 0.15 multiplied by itself five times.

anonymous · Answer

A different question could be, what is the chance that NONE of the five is defective?

The chance that one is defective is 0.15, so the chance that it is NOT defective is 1-0.15 = 0.85.

The chance that all five are not defective is 0.85^5.

See how that works?

anonymous · Answer

Thank you so much