Question

Ravi lends rs. 3600 on simple interest to harsh for a period of 5 years. he lends the part of the amount at 4% interest and the rest at 6% and receives rs. 960 as the amount of interest. how much money did he lend on 4% interest rate?

Answer 1

Solution -

Let the money lend by Ravi to Harsh at 4% simple intrest be Rs x.

Therefore,  money lend by Ravi to Harsh at 6% simple intrest be Rs (3600 - x) 
as total amount lend is Rs 3600.

Now simple intrest at 4% for 5 years 

Principal (P) = Rs x, rate (R) = 4% and Time (T) = 5

SI = PRT/100
    
     = x * 4 * 5/100

    = 20x/100 ---------------1

Now simple intrest at 6% for 5 years 

Principal (P) = Rs (3600 - x), rate (R) = 6% and Time (T) = 5

SI = PRT/100

    = (3600 - x) * 6 * 5 / 100

    = (3600 - x) * 30 /100

    = (108000 - 30x) / 100

Given that, total simple intrest receive = Rs 960.

Therefore, 960 = 20x/100 + (108000 - 30x) / 100

                  960 * 100 = 20x + 108000 - 30x

                   96000 = 108000 - 10x

                    10x = 108000 - 96000

                     10x = 12000

                       x = Rs 1200

Answer - Money lend by Ravi on 4% interest rate is Rs 1200.