Question

GIANNA WAS AWARDED $37,000 FOR WINNING HER SCHOOL COMPETITION. SHE DECIDED TO INVEST HER WINNINGS IN TWO DIFFERENT ACCOUNTS ONE EARNING 4% the other earning 8%interest. If she collect $2480. Of annual interest income, how much did she invest in each account

Answer 1

Answer: Gianna invested $12000 in first account and $25000 in second account .

Explanation:

Given: Total principal amount = $37,000

Interest = $2480

For first year , interest = P x r , where P= principal , r= rate of interest ( in decimal)

For first account , interest rate= 4% = 0.04

Let Principal = x

Interest = 0.04x

For second account , interest rate= 8% =0.08

Let Principal = 37000-x

Interest = 0.08(37000-x)= (0.08)(37000)- 0.08x

= 2960 - 0.08x

Now,
`2960 - 0.08x+0.04x=2480`

`\Rightarrow\ 0.04x=2960 -2480`

`\Rightarrow\ 0.04x=480\\\\\Rightarrow\ x=(480)/(0.04)\\\\\Rightarrow\ x=12000`

Also, 37000-x = 37000-12000 =25000

Hence, Gianna invested $12000 in first account and $25000 in second account .