If Rs.84 invested at a certain rate of simple interest amounts to Rs.96 at the end of 3 years, how much will Rs.105 amount to at the same rate of interest in 5 years?

Explanation:

In the first statement, the principal invested, the number of years for which it is invested and the amount obtained are given. With this information, the rate of interest can be obtained which can be used to calculate the amount asked in the second statement. ‘

Step 1: Amount invested (Prinicipal) P = 84

Number of years n = 3, Amount = 96 – 84 = 12

SI=PNR\100 => 12 = 84×3×r\100

Amount Principal = 96 – 84 = 12 Since, the rate of interest, r = 12×100\84×3=100\21

Step 2: Using the rate of interest, we can find out the amount in the second step.

P – Rs.105, n = 5, r = 100\21

SI = 105×5\100×100\21

Therefore, in five years Rs.205 sill amount to Rs.1310.