Question

ta ( 2500 15 invested for 4 years at 5% compound interest.
(b) 9360 is invested for 3 years at 6% compound interest.​

Answer 1

Correct Question :-

Find the Compound Interest on :-

1. 2500 invested for 4 years at 5% CI.
2. 9360 invested for 3 years at 6% CI.

Solution :-

For the first question :-

Given :-

Principal = 2500

Rate = 5%

Time = 4 years (=> n = 4)

To Find :-

The Compound Interest

Formula :-

$A\: =\: P\:(1\: +\: {\dfrac{r}{100}})^n$

On inserting the values in the formula

We get

$A\: =\: 2500\:(1\: +\: {\dfrac{5}{100}})^4$

$=>\: A\: =\: 2500\:({\dfrac{100 + 5}{100}})^4$

$A\: =\: {\dfrac{2500 \times 105 \times 105 \times 105 \times 105}{100 \times 100 \times 100 \times 100}}$

=> A = 3038.76

CI = Amount - Principal

= 3038.76 - 2500

= 538.76

Therefore, CI is 538.76

For second question :-

Given :-

Principal = 9360

Rate = 6%

Time = 3 years. (=> n = 3)

Formula :-

$A\: =\: P\:(1\: +\: {\dfrac{r}{100}})^n$

On inserting the values in the formula

On inserting the values in the formulaWe get ,

$A\: =\: 9360\:(1\: +\: {\dfrac{6}{100}})^3$

$=>\: A\: =\: 9360\:({\dfrac{100 + 6}{100}})^3$

$A\: =\: {\dfrac{9360 \times 106 \times 106 \times 106}{100 \times 100 \times 100}}$

=> A = 11147.90

CI = Amount - Principal

= 11147.90 - 9360

= 1787.90

Therefore, CI is 1787.90

Short-hands Used :-

• P = Principal
• R = Rate
• T = Time
• A = Amount
• CI = Compound Interest