SOLUTION: 1400=1000(1+(r/360))^720 How do I solve for r?

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: 1400=1000(1+(r/360))^720 How do I solve for r?       Log On


   

Question 17466: 1400=1000(1+(r/360))^720
How do I solve for r?
Answer by bam878s(77) About Me  (Show Source):
You can put this solution on YOUR website!
First, divide both sides by 1000
1400%2F1000 = %281000%281%2B%28r%2F360%29%29%5E720%29
1.4 = %281%2B%28r%2F360%29%29%5E720
Now take log of both sides
log 1.4 = log %281%2B%28r%2F360%29%29%5E720
from the properties of logarithms we know:
log x%5En = n log x
so,
log 1.4 = 720 log 1%2B%28r%2F360%29
Divide both sides by 720
%28log+1.4%29%2F720 = 1+%2B+%28r%2F360%29
%28log+1.4%29%2F720 - 1 = r%2F360
%28%28log+1.4%29%2F720+-1%29+%2A+360 = r
now just use the calculator
hope this helps