Question 1107726: A sum of money lent out at simple interest amounts to 2200in one year and 2800 in 4 years .find the sum of money and rate of interest
You can put this solution on YOUR website! rate is r
x(1+r)=2200
x=2200/(1+r)
we also know
x(1+r)^4=2800
substitute
2200(1+r)^3=2800
(1+r)^3=2800/2200=1.273
1+r=1.084
r=0.084 or 8.4% interest
sum of money is 2200/(1.084)=$2030.06, rounding to end
check by looking for 4 years at 8.4%=$2803, within rounding error.
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