What would be the simple interest obtained on amount of Rs.6,535 at the rate of 10% Percent per annum after 6 years?

A sum of ₹ 800 amounts to ₹ 920 in 3 years at the simple interest rate. If the rate is increased by 3 % p.a., what will be the sum amount to in the same period? 

The difference between C.I and S.I for 2 years is Rs. 9. Find the sum (in Rs.) if the rate is 15% per annum.

A sum of money becomes 3 times in 12 years. In how many years it will become 5 times at the same rate of simple interest?

The simple interest on ₹ 4,000 in 3 years at the rate of x % per annum equals the simple interest on ₹ 5,000 at the rate of 12% per annum in 2 years. The value of x is 

A person lends 40 % of his sum of money at 15 % per annum, 50 % of rest at 10 % per annum and the rest at 18 % per annum rate of interest. What would be the annual rate of interest, if the interest is calculated on the whole sum? 

A man invested Rs.25000 on simple interest at R% p.a. If interest received by man is three twentieth of the principal after three years, then find ‘R’?

The difference of simple interest from two banks on ₹8,000 in 3 years is ₹800. If the rate of interest per annum in two banks are R1 and R2, then what is the value of R1 - R2? (Where R1 > R2)