Answer:
The amount invested at 3–yr CD was $3,600 and the amount invested at 6–month CD was $2,600
Explanation:
Let
x -----> the amount invested at 3–yr CD
x-$1,000 ----> the amount invested at 6–month CD
we know that
The simple interest formula is equal to
where
I is the Final Interest Value
P is the Principal amount of money to be invested
r is the rate of interest
t is Number of Time Periods
in this problem we have
3–yr CD
substitute in the formula above
6–month CD
substitute in the formula above
Remember that
the total amount of interest from these investments was $424.00
so

substitute and solve for x




therefore
The amount invested at 3–yr CD was $3,600 and the amount invested at 6–month CD was $2,600