The product of two numbers is 9375 and the quotient, when the larger one is divided by the smaller, is 15. The sum of the numbers is:

Explanation:-

$$\eqalign{ & {\text{Let}}\,{\text{the}}\,{\text{number}}\,{\text{be}}\,x\,{\text{and}}\,y \cr & {\text{Then}},\,xy = 9375\,{\text{and}}\,\frac{x}{y} = 15 \cr & \frac{{xy}}{{\left( {x/y} \right)}} = \frac{{9375}}{{15}} \cr & \Rightarrow {y^2} = 625 \cr & \Rightarrow y = 25 \cr & \Rightarrow x = 15y = \left( {15 \times 25} \right) = 375 \cr & \therefore {\text{Sum}}\,{\text{of}}\,{\text{the}}\,{\text{number}} \cr & = x + y = 375 + 25 = 400 \cr}$$