Answer:
$10000
Explanation:
Given that:
Molly invested $50,000 in various stocks and bonds.
She earned 15% on bonds and 18% on stocks
Let the bonds be denoted by a
However, her profit on both types of investment is said to be $8700
We are to find how much of the $50,000 did she invest in bonds.
i.e
0.15a + 0.18(50000-a) = 8700
open brackets
0.15a + 9000 - 0.18a = 8700
Collect like terms
0.15a - 0.18a = 8700 - 9000
-0.03a = -300
Divide both sides by(-0.03); we get
a = 10000
Thus, Molly invested $10000 in the bonds.