last year, justin had 30,000 to invest. he invested some of it in an account that paid 5% simple interest per year, and he invested the rest in an account that paid 10% simple interest per year. After one year, he recieved a total of $2500 in interest. How much did he invest in each account?

Answer 1

just add up the interest amounts:

.05x + .10(30000-x) = 2500