This comes from the finan manual, problem 32.7.

John invests 100 at the end of year one, 200 at the end of year two, etc until he invests 1,000 at the end of year ten. The investment goes into a bank account earning 4%. At the end of each year, the interest is paid into a second bank account earning 3%. Calculate the total amount John will have after 10 years.

OK, the first part is simple. Just sum 100+200+....+1000.

After that, I don't get it. So, the interest that gets reinvested looks like this....4, 12, 24, 40....etc..

The only way I can think of to do this is in a series of increasing annuities, each seperated by a year. Is that right? Or is there a faster way? Seems like a little overkill for a problem.

John invests 100 at the end of year one, 200 at the end of year two, etc until he invests 1,000 at the end of year ten. The investment goes into a bank account earning 4%. At the end of each year, the interest is paid into a second bank account earning 3%. Calculate the total amount John will have after 10 years.

OK, the first part is simple. Just sum 100+200+....+1000.

After that, I don't get it. So, the interest that gets reinvested looks like this....4, 12, 24, 40....etc..

The only way I can think of to do this is in a series of increasing annuities, each seperated by a year. Is that right? Or is there a faster way? Seems like a little overkill for a problem.

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