Question

on what sum will the simple interest for 4 years at 3•5 per annum be 28 rupees

Answer 1

Simple interest on any sum remains same every year.
According to the given problem,
Total interest is 28 rupees and time period is 4 years, then interest earned in a single year is (28/4)= 7 rupees.

7 rupees is 3.5 %(rate of interest) of the principal.
Using unitary method, we can find 100% which is = (7/3.5) × 100 = 200 rupees.

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