Exploring Area of Irregular Shapes for Grade 3

The video tutorial reviews the concept of area, focusing initially on regular shapes and how to calculate their area using multiplication. It then introduces irregular shapes, explaining that their area cannot be found by simple multiplication. Instead, it suggests counting unit squares or dividing the shape into rectangles, calculating each area, and summing them up. The tutorial provides examples of both regular and irregular shapes, demonstrating the methods to find their areas effectively.

What is the area of a square with side length 5 units?

• 15 square units

• 25 square units

• 10 square units

• 20 square units

How do you measure the area of a shape?

• Counting the number of sides

• Multiplying length by width

• Adding all angles

• Measuring the perimeter

What unit is used to measure area?

• Kilograms

• Square units

• Cubic units

• Linear units

What is the area of a rectangle with length 7 cm and width 3 cm?

• 21 square cm

• 10 square cm

• 14 square cm

• 24 square cm

What is the area of a rectangle with dimensions 6 inches by 4 inches?

• 24 square inches

• 10 square inches

• 30 square inches

• 20 square inches

Which method can be used to find the area of irregular shapes?

• Using a protractor

• Counting unit squares

• Measuring the diameter

• Calculating the radius

What is the first step in finding the area of an irregular shape by decomposition?

• Measuring the perimeter of each component

• Breaking the shape into regular shapes

• Drawing the shape on grid paper

• Adding the areas of components

What is the area of an irregular shape that can be divided into two rectangles with areas of 40 and 20 square units?

• 120 square units

• 100 square units

• 80 square units

• 60 square units

How do you confirm the area of a decomposed shape?

• By multiplying the areas

• By adding the areas of each part

• By subtracting the smallest area

• By dividing the total area by the number of parts

If an irregular shape is split into three rectangles each with an area of 12 square units, what is the total area?

• 36 square units

• 24 square units

• 48 square units

• 30 square units