Question

The difference between CI and SI on a certain sum at 20% per annum for 4 year is ₹684. Find the sum. ​

Answer 1

Answer:

Step-by-step explanation:

Given:

Rate of interest = 20%

Time = 4 yrs

Difference = 684 [ CI - SI ]

Equation used:

$\purple{si = p * i * t}$

$\red{CI = p(1+i)^n-1}$

Solution:

→ $[p(1+i)^n-1 ] - p * i * t = 684$

→ $[p(1+0.20)^4-1 ] - p * 0.20 * 4 = 684$

→ $[p(1.20)^4-1 ] - p * 0.20 * 4 = 684$

→ $[p (1.0736)] - p(0.8)= 684$

→ $0.2736(p) = 684$

→ $p = 2,500$

Thus the principle amount is 2,500