We can automatically see that we are dealing with a percent decrease because we are going from a smaller to a bigger number. We need to first find what percent of 140the number 84 is. to do this we can set up the following equation:
140/84=100/x (this equation is basically saying if 140 is 100(%) what would 84 be?)
solving for x here gives us x = (84 X 100)/140 = 60, so 84 is 60 percent of 140 which means 140 decreased by 40 percent.
Let me know if I can clear anything else up.
