Investing money

Question

You invested money in two funds. Last​ year, the first fund paid a dividend of​ 9% and the second a dividend of​ 3%, and you received a total of ​$963. This​ year, the first fund paid a​ 10% dividend and the second only​ 1%, and you received a total of ​$825. How much money did you invest in each​ fund?

Answer 1

9F + 3S = 963

10F +S = 825

30F +3S = 2475

9F +3S= 963

21F = 1512

F = 1512/21 = 72 = $7,200 invested in the 1st fund

S = 825-10(72) = 825-720 = 105 = $10,500 invested in the 2nd fund