Aretiree invests $9,000 in a savings plan that pays 5% per year. what will the account balance be at the end of the first year

Using the formula I=Pxrxt
P is the principal amount, $9000.00.
r is the interest rate, 5% per year, or in decimal form, 5/100=0.05.
t is the time involved, 1year(s) time periods.
So, t is 1year time periods.
To find the simple interest, we multiply 9000 × 0.05 × 1 to get that:

The interest is: $450.00
So the balance will be $9450.00 at the end of the first year.