Understanding Grids and Percentages

The video tutorial explains how to calculate the percentage of shaded areas in two different grids. The first grid is a 10x10 grid with 23 shaded squares, resulting in 23% shaded. The second grid is a 10x5 grid with 41 shaded squares out of 50, which is converted to 82% by scaling to a 100-square grid. The tutorial emphasizes understanding percentages as parts out of 100 and demonstrates the calculation process step-by-step.

What is the main task in question seven?

• Identify the number of triangles in a diagram.

• Find the perimeter of a square.

• Determine the percentage of shaded areas in grids.

• Calculate the area of a circle.

How many squares are there across in the first grid?

• 12

• 5

• 8

• 10

What is the total number of squares in the first grid?

• 75

• 50

• 150

• 100

How many squares are shaded in the first grid?

• 15

• 23

• 30

• 45

What percentage of the first grid is shaded?

• 30%

• 15%

• 45%

• 23%

What is the size of the second grid?

• 5 by 5

• 10 by 5

• 10 by 10

• 5 by 10

How many squares are unshaded in the second grid?

• 20

• 25

• 9

• 15

What is the total number of shaded squares in the second grid?

• 25

• 41

• 35

• 30

What is the percentage of shaded area in the second grid?

• 90%

• 82%

• 50%

• 41%

What operation is needed to convert the fraction of shaded squares in the second grid to a percentage?

• Addition

• Subtraction

• Multiplication

• Division