Question

a sum of money lent put at simple interest amounts to ₹2200 in one year and to₹2800 in four years find the sum of money and rate of interest
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Answer 1

Step-by-step explanation:

Sum = P lent out

after one year, Rs 2, 200 = P (1 + r /100 )

After 4 years  Rs 2, 800 =  P (1 + 4 r /100)

Subtract equation 1 from equation 2 :  Rs 2, 800 - RS 2, 200 = 3 P r /100

                                    P r = Rs 20,000

Substituting the value of P r in equation 1 :

          2, 200  = P + 200            So P = Rs 2,000.

            r = 20,000 / 2,000 = 10