Question

Suppose that a classroom has 4 light bulbs. The probability that each individual light bulbs work is 0. 6. Suppose that each light bulb works independently of the other light bulbs. What is the probability that none of the 4 light bulbs work?.

Answer 1

0.0256 or 16/625 or 2.56%

Explanation:

The problem states that each light bulb operates independently of the other, so the probability doesn't change for each light bulb based on how many other light bulbs are working.

The probability of each light bulb working is 0.6 out of 1. However, we want the probability of it being broken.

1 - 0.6 = 0.4

This is the probability of one light bulb being broken. But there are 4 lightbulbs.

We can multiply 0.4 by itself 4 times, as the probability stacks.

0.4 * 0.4 * 0.4 * 0.4 = 0.0256 (Also achieved by raising 0.4 to the power of 4)

To get the percentage, multiply it by 100. 2.56%

0.4 is equal to 40% or 40/100. If you simply, that fraction is equal to 2/5

2/5 * 2/5 * 2/5 * 2/5 = 16/625 (Also achieved by raising 2/5 to the power of 4)