Mrs. Angel. invested $24,000; part at 5%, and part at 8%. The total interest on the investment was $1,680. How much did she invest at each rate?
Pick one:
A) x=$13,000, y =$26,000
B) x=$8,000, y =$16,000
C) x=$14,000, y =$28,000
D) x=$15,000, y =$30,000
E) x=$18,000, y =$36,000
I approached this question like a mixture problem.   I don't like the wordingpartat 5% andpartat 8% because we have variables x and y in the answer choices and I have no idea which one is x or y.   Anyway here's how I did it.   0.05(x) + 0.08(y) = 0.07(x+y)   0.01(y) = 0.02(x)   y = 2x   Note: 0.07(x+y) because $1,680 is 7% of 24,000   In which answer choice is y = 2(x)   Answer x=$8,000, y =$16,000
<result>B</result>
Mrs. Angel. invested $24,000; part at 5%, and part at 8%. The total interest on the investment was $1,680. How much did she invest at each rate?