Question

Ngoc invests a total of $11,000 in two accounts paying 5% and 7% simple interest, respectively. How much was invested in each account if, after one year, the total interest was $620.00.

Answer 1

At 5% amount invested = $7,500

At 7% amount invested = $3,500

Explanation:

We shall create an equation for this.

Let the amount invested with 5 % interest = "x"

Then remaining amount = 11,000 - x, Since total amount invested = $11,000

(x
`*` 5%) + ((11,000-x)
`*` 7%) = $620

0.05 x + 770 - 0.07 x = 620

770 - 620 = 0.07 x - 0.05 x

150 = 0.02 x

`(150)/(0.02)` = x

$7,500 = x

Therefore, amount invested at 5% = $7,500

At 7% = $11,000 - $7,500 = $3,500