Compounding Interest: 1400 = 1000(1 + (r/360))^720

[intervade]

Not sure if I posted in the right board, this is a college algebra class. I'm using the compound interest formula A = P(1+r/n)^nt here is my problem. 1400 = 1000(1 + (r/360))^720 I come up with 720 because t is 2 years. Now I've divided both sides by 1000 and I get 1.4 = (1 + (r/360))^720 if I take the reciprocal of the exponent 720 and multiply it by both sides I get 1.4^(1/720) = 1 + (r/360) .. question is where do I go from here?

 

[DrMike]

Re: Compounding Interest

What are you asked to find? r?

Could you solve 8=2+3x to find x?

Solving 1.4[sup:3slp5ltx](1/720)[/sup:3slp5ltx]=1+r/360 to find r is not much harder. Think about it, and let us know if you're still stuck.

 

[intervade]

Hey I figured the problem out, I wasnt sure about 1.4^(1/720).. I know thats possible but seeing something like that in this class is rare so I was a bit confused. but basically I ended up with 360(1.4^(1/720)-1) and came out to be about %16.