The interest rate tells you how much extra money the bank will put into your account at the end of each year. The formula to find the balance of the account after 1 years is
B(t) = P(1+r) where P is the investment amount and r is the interest rate as a
decimal. Banks list interest rates as percentages, not decimals. To create our formula we
need to convert the percent interest to a decimal.
2. a. Convert your interest rate to a decimal:
(Hint: divide the percent by 100)
45
b. Create an annual compounding function to model the growth of your savings:
(Hint: fill in the general formula with your numbers for P(principal/investment) and
r(rate as a decimal) B(t) = P(1 + r)
b = 1000 (1 +45)
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