5% more is gained by selling a watch for Rs. 350 than by selling it for Rs. 340. The cost price of the watch is

Let cost price of watch = Rs. $$100x$$

When selling price = Rs. 340

=> Profit % = $$\frac{340-100x}{100x} \times 100 = \frac{(340-100x)}{x}$$

Similarly, Profit % when SP = Rs. 350 = $$\frac{(350-100x)}{x}$$

According to ques,

=> $$(\frac{350-100x}{x})-(\frac{340-100x}{x})=5$$

=> $$(350-100x)-(340-100x)=5x$$

=> $$5x=350-340=10$$

=> $$x=\frac{10}{5}=2$$

$$\therefore$$ Cost Price = $$100 \times 2=Rs.$$ $$200$$

=> Ans - (C)