Question

Last year, Goran had $30,000 to invest. He invested some of it in an account that paid 7% simple interest per year, and he invested the rest in an account that paid 10% simple interest per year. After one year, he received a total of $2460 in interest. How much did he invest in each account?

Answer 1

Answer:

He invested $18,000 in the first account

he invested $12,000 in the second account

Explanation:

Let x represent the account that pays 7% simple interest

Let y represent the account that pays 10% simple interest

The sum of x and y gives a  total investment of $30,000

x+y=30000..........1

From interest perspective , we have the below equation as well:

0.07x+0.10y=2460........2

From equation 1

x=30,000-y

substitute for x in equation 2

0.07(30,000-y)+0.10y=2460

2100-0.07y+0.10y=2460

0.03y=2460-2100

0.03y=360

y=360/0.03

y=$12,000

substitute for y in equation 1

x+12,000=30,000

x=30,000-12,000=$18,000