Question

A company gives raises once a year. Amir's present salary is $12,000. His manager would like to raise his salary to $84,000. What percentage raise would he be recieving.

Answer 1

First - What percent is the new salary of the old salary?
100 * (84/12) = 700% Now that was not the question. The question was how much was the "raise" so we subtract off the original 100% and get 600% more than the original.
It is easier to understand if you just consider a 100% raise. That is a doubling so the new is 200% of the old.