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$1,047. This year, the first fund paid a 10% dividend and the second only 1%, and you received a total of $811. How much money did you invest in each fund?

Answer 1

If the amount of money you invested in the first fund is x and the second fund y, then 9% (or 0.09 by moving the decimal 2 spots)*x+0.03*y=1047 since the first fund paid 9% and the second 3%. In addition, for this year, we get 
0.1*x+0.01*y=811. 
We also have 0.09*x+0.03*y=1047, so we can multiply the top equation by -3 and add it to the second to get -0.21x=-1386. Dividing both sides by -0.21, we get x=6600. In addition, since 0.1*x+0.01*y=811, we can plug 6600 in for x to get 660+0.01*y=811 and by subtracting 660 from both sides we get 0.01*y=151. Multiplying both sides by 100 (since 0.01*100=1), we get y=15100