Question

The compound interest on a certain sum for 2 yearsat 10% per annum isrs. 525 . the simple interest on the same sum for double the time at half the rate percent per annum is :

Answer 1

Let the sum be ₹ P.

Given:
R(rate) = 10%, n(time) = 2years
Compound interest (C.I) = ₹525

C.I = [ P (1+ R/100)^n -P]

C.I = P [ 1+ R/100)^n -1]

C.I = P [( 1+ 10/100)² -1

525= P [( 11/10)² - 1 ]

525= P [ 121/100 - 1]

525= P [ (121- 100)/100]

525= P [ 21/100]

P= (525× 100) / 21

P= ₹2500
Sum= ₹ 2500

We know that
S.I =( P× R×T)/100

A.T.Q
Here, P= 2500, R= 5%, T= 4years

S.I = (2500× 5× 4)/100

S.I= ₹ 500

Hence, the simple interest (S.I) = ₹ 500

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Hope this will help you.....