A certain sum of money amounts to 756 rupees in 2 years and to 873 rup

1.	A certain sum of money amounts to 756 rupees in 2 years and to 873 rupees in 3 and a half year at a certain rate of simple interest. What is the rate of interest per annum ? Please don't give incorrect answer I beg you please.
Answer» ong>Answer: $\huge\underline\bold {Answer:}$ Let the initial cost price of the article be 100 rupees. Profit = 20% S.P. of the 1st dealer $= \frac{100 \times 120 }{100} = 120 \: rupees$ Let the second profit % = X. Then, S.P. of the 2nd dealer $= \frac{120 \times (100 + x)}{100}$ Final S.P. of the article after passing through TWO HANDS at a profit = 38% $= \frac{100 \times (100 + 38}{100} = 138$ Given, $\frac{120 \times (100 + 38)}{100} = 138$ $= > 12000 + 120x = 13800$ $= > 120x = 1800 \\ = > x = <klux>15</klux>\%$ So, if the dealer makes a profit of 20%, then the profit per cent made by the second is 15%.