The simple interest on a sum of money is $\frac{4}{9}$ of the principal. Find the rate per cent and time,if both are numerically equal.

The simple interest on a sum is $\frac{1}{16}$ of the principal and the number of years is equal to the rate per cent per annum. The rate per cent per annum is (in $.5$)

With a given rate of simple interest,the ratio of principal and amount for a certain period of time is $4:5$. After $3$ years,with the same rate of interest,the ratio of the principal and amount becomes $5:7$. The rate of interest per annum is (in $\%$):

If the simple interest on a certain sum of money after $6 \frac{1}{4}$ years is $\frac{3}{8}$ of the principal,then the rate of interest (in $\%$) per annum is

For what sum (in ₹) will the simple interest at $R \%$ per annum for $2$ years be $R$?

According to a census report,the population growth rate of Faridabad is going to be an increasing $A.P.$ with the first year's rate as $5 \%$ and common difference as $5 \%$,but simultaneously the migration rate is an increasing $G.P.$ with the first term as $1 \%$ and common ratio of $2$. If the population on $31 \, \text{December}, 2010$ is $1 \, \text{million}$,then find in which year will Faridabad witness its first fall in population?