Customer deposited $ 1250 in his savings bank account. Find the Compou

1.	Customer deposited $ 1250 in his savings bank account. Find the Compound Interest (C.I.) earned by him after 3 years at the rate of 5% per annum.
Answer» Given : PRINCIPLE : $1250 Rate of INTEREST : 5% Time : 3 years To find : The COMPOUND interest. Solution : FIRST, we'll find the amount. $\sf \dashrightarrow Amount = Principle \bigg( 1 + \dfrac{Rate}{100} \bigg)^{Time}$ $\sf \dashrightarrow 1250 \bigg( 1 + \dfrac{5}{100} \bigg)^{3}$ $\sf \dashrightarrow 1250 \bigg( 1 + \dfrac{1}{20} \bigg)^{3}$ $\sf \dashrightarrow 1250 \bigg( \dfrac{20 + 1}{20} \bigg)^{3}$ $\sf \dashrightarrow 1250 \bigg( \dfrac{21}{20} \bigg)^{3}$ $\sf \dashrightarrow 1250 \bigg( \dfrac{21^3}{20^3} \bigg)$ $\sf \dashrightarrow 1250 \bigg( \dfrac{9261}{8000}\bigg)$ $\sf \dashrightarrow 5 \bigg( \dfrac{9261}{32}\bigg)$ $\sf \dashrightarrow \dfrac{9261 \times 5}{32} = \dfrac{46305}{32}$ $\sf \dashrightarrow \cancel \dfrac{46305}{32} = 1447.03125$ Now, we can find the compound interest. Compound interest : $\sf \dashrightarrow Amount - Principle$ $\sf \dashrightarrow 1447.03125 - 1250$ $\dashrightarrow$ ₹ $\sf 197.03125$ Hence, the compound interest is ₹197.03125.