question_answer

Find the rate of interest per annum at which a sum of money becomes double in 8 years.

A)  \[13\,\,\frac{1}{2}%\]               

B)  \[12\,\,\frac{1}{2}%\]

C)  \[11\,\,\frac{1}{2}%\]               

D)  \[10\,\,\frac{1}{2}%\]

E)  None of these