A company fabricates specialpurpose robots and records show

A company fabricates special-purpose robots, and records show that the probability is 0.10 that one of its new robots will require repairs during confirmation tests. What is the probability that the eighth robot it builds in a month is the first one to require repairs?

Explain please

Solution

The probability that it needs repairs is 0.10, so the probability of not needing repair is 1-0.10 = 0.90.

So, the first seven robots do not need repairs (P = 1-0.10) and the eighth one needs repair.

Thus,

P = (1-0.10)^7 * 0.10 = 0.04782969 [ANSWER]