An investment club invested part of $8000 at 10% annual interest the rest at 12%. If the annual income from these investments is $900, how much was invested at each rate
let x be the amount invested at 10% so the amount invested at 12 % = (8000-x) 0.1x + 0.12(8000-x) = 900 0.1x - 0.12x = 900- 960 0.02x = 60 x = 3000 @ 10% 8000 - 3000 = 5000 @ 12%