1/5 of a number exceeds 1/7 of the same number by 10. The number is -

Answer: Option C

Let, the number be 'x'
According to the question
$$\begin{array}{rl}& \frac{1}{5}x-\frac{1}{7}x=10\\ & \frac{7x-5x}{35}=10\\ & 2x=350\\ & x=\frac{350}{2}\\ & x=175\end{array}$$