Investment formula: ONLY works for simple annual interest NOT compounding interest!! VERY important!
I=Prt, where I is the interest earned on the original investment
This is what you are trying to find.
P = amount of original investment
r = annual interest rate
t = time period in years **IMPORTANT: for 1 year, t = 1. If you are asked for just PART of a year, you must divide those number of months by 12 months. For example, if the question asked you for 9 months of interest, t would = 9/12 or .75 years. Got it?
So, you should be able to use the data you are given in the problem and the two equations to figure this out. Come back if you are still stuck.
Good luck on your test!