Simple interest on a certain sum for 6 years is $\frac{9}{25}$ of the sum.The rate of interest is
1). 6%
2). $6\frac{1}{2}$%
3). 8%
4). $8\frac{1}{2}$%
I think it may be Right answer
Rate = $\frac{S.I\times 100}{PRINCIPAL \times TIME}$
$\frac{9}{25}\times\frac{100}{6}$
= 6% per annum
5. The rate of simple interest per annum at which a sum of money double itself in 16⅔ yrs. is
7. If a sum of money at simple interest doubles in 6 years, it will become 4 times in :
8. At what rate of interest is an amount doubled in two years, when compounded annually?
10. In how many years will a sum of money double it self a 12% per annum ?