Given the probability that A can solve a problem is 2 / 3, and the probability that B can solve the same problem is \%, find the probability that
(i)at least one of A and B will solve the problem
(ii)none of the two will solve the problem
Given the probability that A can solve a problem is 2 / 3, and the probability that B can solve the same problem is \%, find the probability that
(i)at least one of A and B will solve the problem
(ii)none of the two will solve the problem

Given : Here probability of A and B that can solve the same problem is given, i.e., P(A)=\frac{2}{3} and P(B)=\frac{3}{5} \Rightarrow P( \bar{A})=\frac{1}{3} and \mathrm{P}(\bar{B})=\frac{2}{5}
Also, A and B are independent. not A and not B are independent.
i) atleast one of A and B will solve the problem
Now, P(atleast one of them will solve the problem) =1 – P(both are unable to solve)
\begin{array}{l} =1-\mathrm{P}(\bar{A} \cap \bar{B}) \\ =1-\mathrm{P}(\bar{A}) \times \mathrm{P}(\bar{B}) \\ =1-\left(\frac{1}{3} \times \frac{2}{5}\right) \\ =\frac{13}{15} \end{array}
Therefore, atleast one of A and B will solve the problem is \frac{13}{15}
ii) none of the two will solve the problem
Now, \mathrm{P} (none of the two will solve the problem) =\mathrm{P}(\bar{A} \cap \bar{B})
=\mathrm{P}(\bar{A}) \times \mathrm{P}(\bar{B})
\begin{array}{l} =\frac{1}{3} \times \frac{2}{5} \\ =\frac{2}{15} \end{array}
Therefore, none of the two will solve the problem is \frac{2}{15}