Steve has Rs. 12000/-, he invested some amount at 10% and rest at 12% simple interest. His income from these investment is Rs.1280/-. How much he invest at 10%?

Answer 1

amount invested at 10% -- x
amount invested at 12% ---- 12000 - x

.10x + .12(12000 - x) = 1280

easy to solve for x