The simple interest of a principal increases by `Rs42.50` when the rate of simple interest per annum increases from `7%` to `7(1)/(2)%`. Find the principal.

If the principal is double in ten years, then the rate of simple interest per annum is

If the interest of a principal in 2 years be (1)/(8) of it, then find the rate of simple interest per annum.

The simple interest of a principal in 1 year and 9 months at the rate of simple interest of 5% per annum is 63Rs more than of the same principal in 2 years and 4 months at the rate of simple interest of 4(1)/(2)% per annum. Find the principal.

The total interest of a principal in n years at the rate of simple interest of r% per. Annum is pnr/25, then the principal will be

What will be the simple interest of a principal of Rs3500 at a rate of 6% simple interest per annum from 5th January to 31 st May, 2012 ?

Find the time in which the simple interest at 2% per annum on a sum of money is (1)/(25) of the principal.

Write True or False If the ratio between principal and amount is 8:9, then the rate of simple interest per annum is 1%.

Determine the total amount of Rs5000 at the rate of 7(1)/(2)% simple interest per annum is 5 years.