Answer:
The woman invested $15,000 at 7% interest rate and $5,000 at 6% interest rate.
Step-by-step explanation:
We are given the following in the question:
Let x be the interest earned from 7% interest rate and y be the interest earned from 6% interest rate.
The woman invested has three times as much invested at 7% as she does at 6%.
Thus, we can write the equation:
The total interest is $1,350.
Thus, we can write the equation:
Solving the two equations by substitution method:
Thus, she invested $15,000 at 7% interest rate and $5,000 at 6% interest rate.