SOLUTION: amount invested: $800 number of compounding periods: 360 annual rate:? accumulated amount: 1200 time (t) in years: 2 r=? do not round until final answer. then round one dec

Algebra ->  Rational-functions -> SOLUTION: amount invested: $800 number of compounding periods: 360 annual rate:? accumulated amount: 1200 time (t) in years: 2 r=? do not round until final answer. then round one dec      Log On


   

Question 256875: amount invested: $800 number of compounding periods: 360 annual rate:? accumulated amount: 1200 time (t) in years: 2
r=?
do not round until final answer. then round one decimal place as needed
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
The formula we need is
A+=+P%281+%2B+r%2Fn%29%5E%28nt%29
P = 800
n = 360
r = ?
A = 1200
t = 2
So we, get
1200+=+800%281+%2B+r%2F360%29%5E%28360%2A2%29
we get
1200+=+800%281+%2B+r%2F360%29%5E%28720%29
divide by 800 to get
1.5+=+%281%2Br%2F360%29%5E720
raise both sides to 1/720 power to get
1.5%5E%281%2F720%29+=+%281%2Br%2F360%29
multiply by 360 to get
360%2A1.5%5E%281%2F720%29+=+360+%2B+r
subtract 360 to get
360%2A1.5%5E%281%2F720%29+-+360+=+r
r ~ .2028 ~ 20.28%