Question

Mr. Wilson invested money in two accounts. His total investment was $40,000. If one account pays 4% in interest and the other pays 8% in interest, how much does he have in each account if he earned a total of $2,720 in interest in 1 year?

Answer 1

invest x at 4%, y at 8%

x + y = 40000
.04x + .08y = 2720


.08x + .08y = 3200
.04x + .08y = 2720

now subtract:

.04x = 480
x = 12000
y = 28000

.04*12000 + .08*28000 = 480 + 2240 = 2720

Answer 2

x + y = 40,000
.04x + 0.08y = 2,720

x = 40,000 - y

.04(40,000 - y) + 0.08y = 2,720

1,600 - .04y + 0.08y = 2,720

1,600 + 0.04y = 2,720

0.04y = 1,120

y = 28,000

x = 40,000 - 28,000

x = 12,000
y = 28,000

Answer 3

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