This is a great worksheet that reinforces mental methods for calculating percentages of amounts.
Section A asks students to complete a table asking for simple percentages such as 10%, 50%, 20% that can be found mentally. The last column of the table is a little more challenging by asking those percentages to be found from a decimal value.
Section B is a set of questions that can all be found using mental methods. This section could be used as a timed challenge.