Bank A offers 6% interest rate per annum compounded half yearly. Bank B and Bank C offer simple interest but the annual interest rate offered by Bank C is twice that of Bank B. Raju invests a certain amount in Bank B for a certain period and Rupa invests Rs. 10,000 in Bank C for twice that period. The interest that would accrue to Raju during that period is equal to the interest that would have accrued had he invested the same amount in Bank A for one year. The interest accrued, in INR, to Rupa is

The interest from Bank A for one year at 6% compounded half-yearly on Rs. P is P times (1.03 squared minus 1), which is 0.0609P. Equating this to Raju's simple interest gives R times B times 1 divided by 100 equals 0.0609P, meaning R times B equals 6.09P. Rupa invests Rs. 10,000 in Bank C at twice the rate for twice the period, so her interest is 10000 times (2B) times (2 times 1) divided by 100, equaling 400B. Substituting B equals 6.09P divided by R into Rupa's interest gives 400 times 6.09P divided by R, which equals 2436 times (P divided by R); since P divided by R is 1, her interest is Rs. 2,436.

• Thanks
• Wrong explanation