Task: Question Answering
Input (English): Problem: if money is invested at r percent interest, compounded annually, the amount of the investment will double in approximately 24 / r years. if pat ' s parents invested $ 6,000 in a long - term bond that pays 8 percent interest, compounded annually, what will be the approximate total amount of the investment 18 years later, when pat is ready for college ?
Options: a. $ 20000, b. $ 15000, c. $ 12000, d. $ 10000, e. $ 30000
Output (English): e