An investment advisor is planning the retirement of a customer. The customer has $10,000 dollars to invest and needs the investment to increase to $30,000 within 20 years...so 20 years or less.

Now I need to figure out 2 investment plans to make the above numbers work themselves out. I am so incredibly frustrated. I thought of the compound interest formula, but the problem does not tell me how many times a year the investment can or should be compounded.

Can someone please shed some light? I really need help!

Thanks is advance!