Question

A certain sum of money amounts to Rs5292 in 2years and Rs5556.50 in 3years, interest being compounded annually, Find the rate percent and the sum

Answer 1

for the third year,
P = 5292
SI = 5556.50 - 5292 = 264.5
t = 1 year

SI = Ptr/100
⇒ 264.5 = 5292×1×r/100
⇒ r = (264.5×100)/5292 = 5%

5292 = P(1+ 5/100)²
⇒ 5292 = P(1.05²)
⇒ P = 5292/1.05²
⇒ P = 4800

Sum = Rs. 4800
rate = 5%

Answer 2

In the third year,

Principle (P) = Rs. 5292
Simple Interest (SI) = Rs. (5556.50 - 5292) = Rs. 264.5
time (t) = 1 year

SI = (P×t×r)÷100
⇒ 264.5 = (5292×1×r)÷100
⇒ r = (264.5×100)÷5292 = 5%

5292 = P(1+ 5/100)²
⇒ 5292 = P(1.05²)
⇒ P = 5292/1.05²
⇒ P = 4800

Amount = Rs. 4800
Rate of Interest per annum= 5%