Suppose A and B are two events such that $P(A\cap B)=\frac{3}{25}$ and $P(B-A)=\frac{8}{25}$. Then $P\left(B\right)=$

Given $A,B$ are two events such that $P(A\cap B)=\frac{3}{25}$ and $P(B-A)=\frac{8}{25}$

We know that  $\begin{array}{rcl}P\left(B-A\right)& =& P\left(B\right)-P\left(B\cap A\right)\end{array}$

Subsitute the appropriate values in the above equation 

    $\begin{array}{rcl}\frac{8}{25}& =& P\left(B\right)-\frac{3}{25}\\ P\left(B\right)& =& \frac{8}{25}+\frac{3}{25}\\ & =& \boxed{\frac{11}{25}}\end{array}$