18. Five mark exercise problem VI

The probability that a person will get an electrification contract is $\frac{3}{5}$ and the probability that he will not get plumbing contract is $\frac{5}{8}$. The probability of getting atleast one conract is $\frac{5}{7}$. What is the probability that he will get both?

 

Answer:

 

The required probability is $\frac{i}{i}$