A man invests his savings in two accounts, one paying 6% and the other paying 10% simple interest per year. He puts twice as much in the lower-yielding account because it is less risky. His annual interest is $10296 dollars. How much did he invest at each rate?
Amount invested at 6% equals = ???
Amount invested at 10% equals = ???
x = amount at 10%
2x = amount at 6%
so now you just add up the interest:
0.06 * 2x + 0.10 * x = 10296
Now just solve for x