Home / Arithmetic Aptitude / Compound Interest :: Discussion

### Discussion :: Compound Interest

1. The difference between simple and compound interests compounded annually on a certain sum of money for 2 years at 4% per annum is Re. 1. The sum (in Rs.) is:

2.  A. 625 B. 630 C. 640 D. 650

Explanation :

Let the sum be Rs. x. Then,

C.I. =$$[ X (1+(\frac { 4 } { 100 } ) ^2 -X]$$=$$( \frac { 676 } { 625 } X$$-X)=$$\frac { 51 } { 625} X$$

S.I. =$$[\frac { XX4X2 } { 100 } ]$$=$$\frac { 2X } { 25 }$$

$$\frac { 51 } { 625} X$$-$$\frac { 2X } { 25 }$$=1

x = 625.

Be The First To Comment