The probability that a person will get an electrification contract ia (2/5) and the probability that he will not get a plumbing contract is (4/7). If the probability of getting at least one contract is (2/3), what is the probability that he will get both?
Let A denote the event that a person will get electrification contract and B denote the event that the person will get a plumbing contract
Given : P(A) = 
, P(not B) = P(
) = 
, P(A or B) = 
To find: Probability that he will get both electrification and plumbing contract = P(A and B)
Formula used : P(B) = 1 – P(
)
P(A or B) = P(A) + P(B) - P(A and B)
P(B) = 1 - 
P(B) = 
Probability of getting at least one contract = 
P(A and B)
P(A and B)
P(A and B) 
P(A and B) 
The probability that he will get both electrification and plumbing contract = 