Step by step
The question
Question: $1500 is deposited at the end of each year into an account paying 6% compounded yearly.
How much is in the account after 25 years?
1 Read the numbers
PMT is the money put in each time: $1500.
r is the yearly rate: 6% is 0.06.
n is how many times a year: once.
t is the time: 25 years.
2 Per payment
Interest is added each year.
The rate for one year is i: r over n.
0.06 divided by 1 is 0.06.
And N is how many deposits: 1 times 25 is 25.
3 Use the formula
The future value FV is what the account holds at the end: PMT times, (1 + i) to the power N, minus 1, over i.
We put the numbers in: 1 plus 0.06 is 1.06.
4 Work it out
With a calculator, 1.06 to the power 25 is about 4.29187.
Minus 1, divided by 0.06: about 54.8645.
So FV is 1500 times 54.8645.
Money is rounded to cents: about 82296 dollars and 77 cents.
Careful!
That is only the money put in.
It leaves out all the interest.
5 Check
Let's check.
The deposits alone are 1500 times 25: $37500.
The account has more, because of the interest.
The interest earned is 44796 dollars and 77 cents.
So it makes sense!
Let's look back.
First: read the numbers.
Then: per payment.
Then: use the formula.
Then: work it out.
Last: check.