Which of the following fractions will be added to fraction $6\frac{3}{5}$ to get 15?

According to the question, the required fraction will be equal to the difference between$6\frac{3}{5}$ and 15.

Therefore,

$15-6\frac{3}{5}$

$=15-\frac{33}{5}$

$=\frac{\left(15\times 5\right)-33}{5}$  [L.C.M. (1,5) = 5]

$=\frac{75-33}{5}$

$=\frac{42}{5}$

$=8\frac{2}{5}$

Therefore, the fraction should be added to $6\frac{3}{5}$ to get 15 is  $\mathbf{8}\frac{\mathbf{2}}{\mathbf{5}}$.