Yumiko invests $2300 in a Certificate of Deposit at 5.2% interest compounded 4 times per year.

  1. Find the equation that represents the account balance at time LaTeX: \displaystyle t .
  2. When will the account double? e.g. when will it be $4600. Round your solution to the nearest tenth of a year.

  1. Using the compounded interest formula gives LaTeX: \displaystyle A = 2300 \cdot 1.013^{4 t} .
  2. It will take about 13.4 years.