A circuit to run a model railroad has 8 switches. two are defective. if a person selects 2 switches at random and tests them, find the probability that the second one is defective, given that the first one is defective.
Accepted Solution
A:
If you know there are exactly two defective switches and you have already selected one of them of 8 total, then there is one left out of 7 remaining.Β Β