Question

You invested a total of $12,000 at 4.5 percent and 5 percent simple interest. During one year, the two accounts earned $570. How much did you invest in each account?

Answer 1

Answer: You invested $6000 in both accounts.

Step-by-step explanation:

Let x represent the amount invested in the account earning 4.5% interest.

Let y represent the amount invested in the account earning 5% interest.

You invested a total of $12,000 at 4.5 percent and 5 percent simple interest. This means that

x + y = 12000

The formula for simple interest is expressed as

I = PRT/100

Where

P represents the principal

R represents interest rate

T represents time in years

I = interest after t years

Considering the account earning 4.5%

I = (x × 4.5 × 1)/100 = 0.045x

Considering the account earning 5%

I = (y × 5 × 1)/100 = 0.05y

During one year, the two accounts earned $570. . This means that

0.045x + 0.05y = 570 - - - - - - - - - - 1

Substituting x = 12000 - y into equation 1, it becomes

0.045(12000 - y) + 0.05y = 570

540 - 0.045y + 0.05y = 570

- 0.045y + 0.05y = 570 - 540

0.005y = 30

y = 30/0.005 = 6000

x = 12000 - y = 12000 - 6000

x = $6000