Question

Simone invests 1200 into two savings accounts. One account earns 4% annual interest and the other earns 5.9% annual interest. At the end of 1 year, Simon earned 64.15 in interest. How much did he invest at each rate

Answer 1

Answer: He invested $350 at 4% and $850 at 5.9%

Step-by-step explanation:

Let x represent the amount which he invested in the account earning 4% interest.

Let y represent the amount which he invested in the account earning 5.9% interest.

Simone invests 1200 into two savings accounts. One account earns 4% annual interest and the other earns 5.9% annual interest. This means that

x + y = 1200

The formula for determining simple interest is expressed as

I = PRT/100

Considering the account earning 4% interest,

P = $x

T = 1 year

R = 4℅

I = (x × 4 × 1)/100 = 0.04x

Considering the account earning 5.9% interest,

P = $y

T = 1 year

R = 5.9℅

I = (y × 5.9 × 1)/100 = 0.059y

At the end of 1 year, Simon earned 64.15 in interest. it means that

0.04x + 0.059y = 64.15 - - - - - - - - -1

Substituting x = 1200 - y into equation 1, it becomes

0.04(1200 - y) + 0.059y = 64.15

48 - 0.04y + 0.059y = 64.15

- 0.04y + 0.059y = 64.15 - 48

0.019y = 16.15

y = 16.15/0.019

y = 850

x = 1200 - y = 1200 - 850

x = 350