**A man purchased a watch for Rs. 400 and sold it at a gain of 20% of the selling price. The selling price of the watch is:__________?**

A. Rs. 300

B. Rs. 320

C. Rs. 440**D. Rs. 500**

Explanation:

Let S.P = Rs. X

Then, 400 + 20% of x = x

(Or) 400 + X/5 = X

(Or) 4X/5 = 400

(or) x = 400 × 5/4 = 500

S.P = Rs. 500