Simple Interest with Explanation

Q15. If Rs. 64 amounts to Rs. 83.20 in 2 years, find the value that Rs. 86 will amount to in 4 years at the same rate of interest?

Answer- Option A

Explanation-

P = Rs. 64, S.I. = Rs. (83.20 - 64) = Rs. 19.20, T = 2 years
So, rate =

100 x 19.20 62 x 2

% = 15%

Now, P = Rs. 86, R = 15%, T = 4 years.
S.I. = Rs.

86 x 15 x 4 100

= Rs. 51.60.

Q16. Suresh invested in all Rs. 2600 in three different schemes at 8%, 4%, and 6% per annum simple interest. At the end of the year, he received the same interest in all the three schemes. What is the money invested in scheme having 4% rate of interest?

Answer- Option B

Explanation-

Let the parts be x, y, and [2600 - (x + y)]. Then,

x*4*1 100

=

y*6*1 100

=

[2600 - (x + y)]*8*1 100

y x

=

4 6

y =

2x 3

Putting the value of y in the above equation, we obtain x = Rs. 1200