Question

Susan invested part of her $15,000 bonus in a find that paid and 11% profit and invested the rest in stock that suffered a 5% loss. Find the amount of each investment if her overall net profit was $850.

Answer 1

• $10,000 in the 11% fund
• $5,000 in the stock

Explanation:

Let f and s represent the amounts invested in the fund and in stocks, respectively. The problem statement gives rise to two equations:

f + s = 15000 . . . . . . . Susan invested a total of 15000

0.11f + (-0.05)s = 850 . . . . . her total return was 850

These can be solved by any of a variety of methods. Using elimination, we can multiply the second equation by 20 and add it to the first:

20(0.11f -0.05s) +(f + s) = 20(850) +15000

3.2f = 32000 . . . . . . . . . simplify

f = 10000

s = 15000 -f = 5000

Susan invested $10,000 in the fund and $5,000 in stock.