SOLUTION: Mrs Stuart invested part of $4200 at 7% and the rest at 7.5%. If her total annual income from these investments was $306, how much did she invest at each rate?

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Question 323430: Mrs Stuart invested part of $4200 at 7% and the rest at 7.5%. If her total annual income from these investments was $306, how much did she invest at each rate?
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
.075X+.07(4,200-X)=306
.075X+294-.07X=306
.005X=306-294
.005X=12
X=12/.005
X=2,400 AMOUNT INVESTED @ 7.5%.
4,200-2,400=1,800 AMOUNT INVESTED @ 7%.
PROOF:
.075*2,400+.07*1,800=306
180+126=306
306=306