Question

In a square sheet of 1,000 grids, 20% of the grids are shaded. How many more grids should be shaded so that 50% of the grids are shaded?

• A. 400
• B. 300
• C. 200
• D. 500

Answer 1

The correct option is B 300

Total number of grids = 1,000

Number of grids shaded
= 20% of 1000
$=\frac{20}{100}\times$ 1000
= 200

If 50% is shaded, then the number of grids that is shaded,
= 50% of 1000
$=\frac{50}{100}\times$ 1000
= 500

Hence, 500 - 200 = 300 more grids need to be shaded so that 50% of the grids are shaded.