Need a custom math course? Visit http://www.MathHelp.com. This lesson covers percent of a number. Students learn to find a percent of a number. For example, to find 65% of 40, first rewrite 65% as the decimal 0.65, and "of 40" means "times 40", so we have 0.65 x 40, which equals 26. So 65% of 40 is 26.