The bankers discount on Rs 1800 at 12% per annum is equal to the true discount on Rs 1872 for the same time at the same rate. Find the time.

The banker's discount on Rs1800 at 12%per annum is equal to the true discount on Rs 1872 for the same time at the same rate.Find the time.

The banker's discount on Rs1600 at 15% per annum is the same as true discount on Rs 1680 for the same time and at the same rate. The time is (a) 3 months months (d) 8 months

The interest on a certain sum of money is Rs 22 and the true discount on the same sum for the same time and at the same rate is Rs 20. Find the sum.