Final answer:
To find the percent of pencils that don't have an eraser, divide the number of pencils without an eraser by the total number of pencils in the box and multiply by 100. In this case, the percent of pencils without an eraser is 35%.
Step-by-step explanation:
To find the percent of pencils that don't have an eraser, divide the number of pencils without an eraser by the total number of pencils in the box and multiply by 100. In this case, there are 21 pencils without an eraser out of 60 pencils total. So, the percent of pencils without an eraser is:
(21 / 60) x 100 = 35%
Therefore, 35% of the pencils in the box don't have an eraser.