Aptitude Day 186

Problems on Simple Interest:

1. The simple interest on a sum of money is 25/49 of the principal. Find the rate percent and time, if both are numerically equal.

Solution:

                Let the sum be x.

                T = R  and S.I = (25/49)x [Given]

                S.I = PTR/100

                (25/49)x =(x*R*R)/100

                 25*100/49 = R²

                 R = 5*10/7

                 R = 7(1/7)*

                 T = 7 Years 2 months approximately.

2. A sum of 1500 is lent out into 2 parts, one at 6% and another one at 2%. If the total annual income is 50, find the money lent at each rate.

Solution:

                 Let the sum lent at 2 parts be x and 1500-x.

                 S.I = PTR/100

                 50 = x*1*6/100 + (1500-x)*1*2/100

                 5000 = 6x+3000-2x

                 4x = 2000

                 x = 500.

                 1500-x = 1000.

                The money lent at each rate are 500 and 1000.