You can put this solution on YOUR website! For this problem, you'd use the "compounding" formula:
"x" is the future amount of money. That's what we're solving for. (x=???)
"P" is the orignal amount (p=$400)
"i" is the rate of compounding interest each period. The problem says 13%, but how often does it compound? Monthly. So you need to divide it by 12.
"n" is the number of compounding periods. The problem gives you 8 months, and thankfully it's compounded monthly, so nothing to do here (n=8)
Then it's just a matter of plugging in your pieces back into the formula, and solving for X.
After 8 months, you would have $436.01.
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