A mother wants to invest $9,000.00 for her son’s future education. She invents a portion of the money in a bank certificate of deposit (Cd account) which earns 4% and the remainder in a saving bond that earns 7%. If the total interest earned after one year is $540.00, how much money was invested in the CD account?

2 answers

$X-Invested in CD.
$Y-Invested in bonds.

Eq1: 0.04X + 0.07Y = $540.
Eq2: X + Y = $9000.
Multiply Eq1 by 100 and Eq2 by -7:

4X + 7Y = 54000.
-7X -7Y = -63000.
Add the Eqs:
-3X = -9000.
X = $3000 Invested in a CD.
Jamal currently earns $20,000 a year in gross wages. On January 1, he is due to receive a 2% COLA. What will his gross income be after the COLA takes effect?