A maintenance firm has gathered the following information regarding the failure mechanism for 100 air conditioning systems:


Evidence of Gas Leaks

Yes No

Evidence of electrical failure Yes 53 9

No 35 3


The units without evidence of gas leaks or electrical failure showed other types of failure. If this is a representative sample of AC failure. Find the probability:


a. That a failure involves a gas leak.

b. That there is evidence of electrical failure given that there was a gas leak.

c. That there is evidence of a gas leak given that there is evidence of electrical failure.