SOLUTION: In investing $5,750 of a couple's money, a financial planner put some of it into a savings account paying 3% annual simple interest. The rest was invested in a riskier mini-mall de

Question 918985: In investing $5,750 of a couple's money, a financial planner put some of it into a savings account paying 3% annual simple interest. The rest was invested in a riskier mini-mall development plan paying 10% annual simple interest. The combined interest earned for the first year was $421. How much money was invested at each rate?
Answer by richwmiller(17219) (Show Source): You can put this solution on YOUR website!
Total amount of money invested: $5750
x+y=5750,
Total yearly interest for the two accounts is: $421
0.03*x+0.1*y=421
x=5750-y
Substitute for x
0.03*(5750-y)+0.1*y=421
Multiply out
172.5-0.03*y+0.1*y=421
Combine like terms.
0.07*y=248.5
Isolate y
y=$ 3550.00 at 10% earns $355 interest
x=5750-y
Calculate x
x=$ 2200.00 at 3% earns $66 interest
Check
0.03*2200+0.1*3550=421
66+355=421
421=421
If 421=421 is TRUE and neither x nor y is negative then all is well
codeint1

RELATED QUESTIONS
In investing $5,650 of a couple's money, a financial planner put some of it into a... (answered by CPhill)

In investing $5,900 of a couple's money, a financial planner put some of it into a... (answered by addingup)

In investing $5,900 of a couple's money, a financial planner put some of it into a... (answered by ikleyn,greenestamps)

In investing $6,600 of a couple's money, a financial planner put some of it into a... (answered by richwmiller)

In investing $6,950 of a couple's money, a financial planner put some of it into a... (answered by jerryguo41)

In investing $6,100 of a couple's money, a financial planner put some of it into a... (answered by ikleyn)

In investing &5500 of a couples money, a financial planner put some of it into savings... (answered by josmiceli,MathTherapy,greenestamps)

1. Mike�s Sport Shop deposits $3,600 at the end of each year for 12 years at 7% annual... (answered by edward d,Hyot)

An investing advisor put 75% of a client's money into a money market fund with a 9%... (answered by ikleyn,greenestamps)