Question based on cost price, market price and discount One merchant correctly calculates his profit percentage on the cost price; another wrongly calculates it on the selling price. Find the difference in the actual profits if both claims to make 30% profit, and their revenue is 3900. Correct profit percentage is $P/C.P*100=30$ Wrongly calculated profit $P/S.P*100=30$ $P/3900*100=30$ which gave me $1170$ How to calculate profit from correct profit percentage? Also, let me know if I am doing it right

**Hint:**

The profit in the first case is $P_1=\frac{3900-C_1}{C_1}=0.3$

And the profit in the second case $P_2=\frac{3900-C_2}{3900}=0.3$