Fill in the blanks :$P(A)=\large\frac{1}{3}$$,P(B)=\large\frac{1}{5}$$,P(A\cap B)=\large\frac{1}{15}$$,P(A\cup B)$=____________

Question

$\begin{array}{1 1}(A)\;\large\frac{7}{15}\\(B)\;\large\frac{8}{15}\\(C)\;\large\frac{6}{15}\\(D)\;\large\frac{4}{15}\end{array} $