Question

Mary deposited $350 in a bank account that promises 2.8 percent interest compounded continuously. Approximately how many years will it take to reach a balance of $500?

Answer 1

Continuous interest tells you that you will use the interest formula that involves e.
\[A=Pe ^{rt}\]
A is the future value. P is the starting value. r is the rate as a decimal. t is the number of years of the investment.
You will need to use ln to get the exponent to "come down" so the equation becomes easier to manage. More help?