a) The formula for compound interest is:
Total = starting amount x (1 + interest rate)^ number of years
b)
Using the given information you have:
1200 = 500 x (1+0.045)^x where x is the length of time you want to find.
1200 = 500 (1.045)^x
Divide both sides by 500:
2.4 = 1.045^x
Use natural logarithms:
ln(1.045^x) = ln(2.4)
Solve for x:
X = ln(2.4) / ln(1.045)
X = 19.889 years ( Round the answer as needed).
