I am looking for the formula for Compounded Interest for the following problem:

I am having a really hard time with some of my assignments because I am not sure the formula I found is correct - it does not seem to be giving me the correct answer.

The question is as follows:

You deposit $4,000 in the bank at the end of each year for 30 years.If the bank pays interest of 5.25% per annum, what would you have accumulated if interest is compounded:

a.Annually

b.Biannually

c.Quarterly

d.Monthly

e.Daily

I have to show my work.

The formula I was able to find is as follows:

Dep x (((1 + (r/n))^n(t) -1) / (r/n))

So annually -

4000 x (((1 + (0.0525 / 1)¹⁽³⁰⁾ -1) / (0.0525 / 1)) =

4000 x (((1 + 0.0525)³⁰ -1) / (0.0525)) =

4000 x (3.64155109 / 0.0525) =

4000 x 69.3628779 = $277,451.51

The answer should be:You would have contributed $124,000.00.Interest earned $186.583.Total in account after 30 years $314,647.11.

This is according to the compounded calculator - but I have to show my work.

Any help you could give me on what the formula would look like for each period above would be wonderful.

Teresa Miller