In 5 years, the simple interest on an amount of Rs. X is $$2\over 5$$ of the principal. The rate of interest per annum is:

What will be the ratio of the interests earned by identical sum of money invested at the same rate of simple interest for 6 years and for 15 years respectively?

A certain sum amounts to ₹15,500 in 2 years at 12% p.a. simple interest. The same sum will amount to what in$$1{1\over 2}$$ years at 10% p.a., if the interest is compounded half yearly (nearest to ₹1)?

There is 80% increase in an amount in 8 years at simple interest. What will be the compound interest on Rs. 15,000 after 3 years at the same rate of interest?

At what rate of simple interest will a sum of money double in 8 years?

On a sum Rina earn a interest of Rs. 1519 at S.I. in 7 years at 7% p.a. Find the sum.

What sum of money must be given as simple interest for six months at 4% per annum in order to earn 150 interest?

Mohan lent some amount of money at 9% simple interest and an equal amount of money at 10% simple interest each for two years. If his total interest was Rs. 760, what amount was lent in each case?