Question

In how much time will a sum of Rs.$1600$ amount to $1852.20$ at $5$% per annum compound interest.

Answer 1

Interest for first year $=\frac{1600\times 5\times 1}{100}=80$

Amount after first year $=1600+80=1680$

Interest for second year $=\frac{1680\times 5\times 1}{100}=84$

Amount after second year $=1680+84=1764$

Interest for third year $=\frac{1764\times 5\times 1}{100}=88.2$

Amount after first year $=1764+88.2=1852.2$

Thus, time required $=3years$