Question on Earnings and Investments

Topic : Earnings and Investments

Question : Zane has four times more money invested at 9% than in another bank where 6% is earned for the year. If Zane earned $5040 in interest for the year, how much does Zane have invested at 9% ?

Solution:
Let the amount invested at 6% be x
and the amount invested at 9% = 4x
given total interest earned for the
year = $5040
4x times 9% + x times 6% = 5040
36x/100 +6x/100 = 5040
42x/100 = 5040
x = 504000/42 = 12,000
4x = 4 * 12,000 = $48,000

Amount invested at 9% = $48,000 (Answer)