Whitney's two student loans totaled $14,000. One of her loans was at 5% interest and the other at 7%. Whitney owed $850 in interest. Amount of each loan?

Question

Final exam tomorrow. I can't figure out these review word problems for the life of me. 

Answer 1

a + b = 14,000 -----> a = 14,000 - b

0.05a + 0.07b = 850

 

0.05(14,000 - b) + 0.07b = 850

700 - 0.05b + 0.07b = 850

0.02b = 150

b = 7500

 

a = 14,000 - 7500

a = 6500