At what rate of simple interest, the sum of $₹4500$ will be $₹5400$ after three years?

At $10.5\%$ p.a. simple interest, the interest on a certain sum on a certain period is $₹2835$. The interest on it for six months is $₹236.25$. What is the sum?

A sum of $₹2400$ amounts to $₹3264$ in four years at a certain rate of simple interest. If the rate of interest is increased by $1\%$, the same sum at the same time would amount to?

What will be the difference between the simple interest and compound interest on $₹8000$ at the rate of $5$ p.c.p.a. at the end of three years?

At what rate of simple interest will $₹8000$ fetch interest of $₹2000$ at the end of four years?

A sum fetched total simple interest of $₹5950$ at the rate of $8.5$ percent per annum in $5$ years. What is the sum?