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Devante invests $4000 in two different accounts. The first account paid 6 %, the second account paid 11 % in interest. At the end of the first year he had earned $320 in interest. How much was in each account?

$
at 6 %

$
at 11 %

User Irmak
by
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1 Answer

3 votes

Answer:

Let x represent the amount of $ in the 4% account and y in the 2% account.

Then x + y = $4000 (total savings).

Interest at 4% would be x*0.04*1 = 0.04x, and

Interest at 2% would be y*0.02*1 = 0.02y.

Then 0.04x + 0.02y = $140 interest, total.

We must solve this system of linear equations.

Mult. 0.04x + 0.02y = $140 by 100 to remove the fractions:

4x + 2y = $14000 We already know that x + y = $4000, so y = $4000-x.

Then 4x + 2y = $14000 becomes 4x + 2($4000-X) = $56000.

Simplifying, 4x + $8000 - 2x = 14000.

2x = $6000

x = $3000 at 4%

y = $1000 at 2%

i hope it helps :)

Explanation:

User Renato Aquino
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