# Mrs. Bennett has graded 20% of her 150 students' papers. How many papers does she still need to finish grading?

Nov 17, 2016

$120$ papers are left to be graded.

#### Explanation:

You can start by either calculation how many she has done already, or by calculating what percent is left still to do.

Find 20% " of " 150

$\frac{20}{100} \times 150 = 30$ papers are done.

$150 - 30 = 120$ papers are still left to do.

OR:

If 20% are done, then 100%-20% = 80% are still left.

Find 80% " of "150

$\frac{80}{100} \times 150 = 120$ papers are still left