You can
put this solution on YOUR website!Jan invested $1200 at a certain simple interest rate and $2200 at a rate 3% higher. Her annual earnings were $253. Find the two interest rates if she earned $121 more on the larger investment than on the smaller.
:
You don,t need the last statement:
:
Let x = interest rate (in decimal form) of the $1200 investment
Then
(x+.03) = interest rate of the $2200 investment
:
1200x + 2200(x+.03) = 253
:
1200x + 2200x + 66 = 253
:
3400x = 243 - 66
:
3400x = 187
x =
x = .055, 5.5% int rate on the $1200
then
.055 +.03 = 8.5% int rate on the $2200
:
Check:
.055 * 1200 = 66
.085 * 2200 = 187
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total int: = 253
:
:
187 - 66 = 121, proves the last statement is true, but we did not need it
