Math
posted by Monica on .
If the principal P = $900, the interest I = $882, and time t = 7 years. What is the rate? What is the future value?

I will assume "simple interest", even though for 7 yrs that is very unusual
Rate = Interest/(prinicipal x time)
= 882/(900(7))
=.14
or 14%
check: I = PRT = 900(.14)(7) = 882
if it is compound interest ....
1782 = 900(1+i)^7
1.98 = (1+i)^7
take 7th root
1.102525 = 1+i
i = .102525
the annual rate would be 10.25%
this shows the tremendous difference between simple and compound interest over a significant time