
Roberto C. answered 12/02/12
Highly Qualified Teacher - Algebra, Geometry and Spanish
Let:
x = amount invested in fund 1, which earned 7% and
y = amount invested in fund 2, which earned 2%
Set up a system of 2 equations:
The total amount invested is the sum of the amounts invested in fund 1 plus the amount invested in fund 2:
I - x + y = 2,900
The total interest earned is the sum of the interest earned by fund 1 plus the interest earned by fund 2:
II - 0.07x + 0.02y = 148
Solve for x in equation I: x = 2,900 - y
Substitute x in equation II: 0.07(2,900 - y) + 0.02y = 148
Solve for y: 203 - 0.07y + 0.02 y = 148
-0.05y = -55
y = 1,100
Since y represents the amount invested in fund 2, we may now write the answer:
The amount invested in fund 2, which earned 2% was $1,100
The amount invested in fund 1, which earned 7% was $1,800
Now check your answer:
Total amount invested: $1,100 + $1,800 = $2,900
Total interest earned: $1,100(0.02) + $1,800(0.07) = $148