Task: Question Answering
Input (English): Problem: if the simple interest on a sum of money for 2 years at 5 % per annum is rs. 50, what is the compound interest on the same sum at the rate and for the same time ?
Options: a. rs. 51.25, b. rs. 51.27, c. rs. 51.79, d. rs. 51.8, e. rs. 51.93
Output (English): a