Answer:
$ 500 was the principal of the loan at 4%, and $ 2,500 was the principal of the loan at 3.5%.
Explanation:
Given that Eric borrowed a total of $ 3000 from two student loans, and one loan charged 4% simple interest and the other charged 3.5% simple interest, both payable after graduation, if the interest he owed after 2 years was $ 215, to determine the amount of principal for each loan, the following calculation must be performed:
4 x 2 = 8
3.5 x 2 = 7
1500 x 0.08 + 1500 x 0.07 = 225
1400 x 0.08 + 1600 x 0.07 = 224
100 x 0.08 + 2900 x 0.07 = 211
500 x 0.08 + 2500 x 0.07 = 215
Therefore, $ 500 was the principal of the loan at 4%, and $ 2,500 was the principal of the loan at 3.5%.