Question

In how many years will a sum of money double itself at 4% per annum ?

• A. 8 years
• B. 16 years
• C. 12 years
• D. 25 years

Answer 1

Answer: (D)

25 years

Let sum $=x$. Then, S.I. $=x$.
$\therefore$ Time $=\frac{100\times S.I.}{Sum\times Rate}$
$=\left(\frac{100\times x}{x\times 4}\right)=25$ years