40 squares are shaded in a 100-square grid.

What percentage of the grid is shaded?

40%

Step-by-step explanation:

40 squares are shaded out of 100 squares so you will apply a fraction - 40/100. To get the answer as an percentage, you need to multiply your original fraction by 100. That means you will do 40/100 x 100, which gives you 40%.