Bev went to lunch with some friends. the bill, including tax, was $20. bev left a tip of $5.
what percent of the bill did bev leave as tip?

In order to find the percent tip, you divide the amount left by the total amount of the bill:
$5 tip/$20 bill = 0.25
In order to change this into a percent, you need to multiply this 0.25 by 100, so the percent tip left is 25% of the bill