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What is area?
Textbook: Part 3, lesson 81, pp. 20–21
GoalThe idea of area: how much space a shape covers; comparing areas with a common measure.
New words
area · yuzmeasure · o‘lchovsquare unit · katakcomparing · solishtirish
Explanation
Area tells how much space a shape covers on a plane. To compare two areas we measure both with the same unit, for example one square. The area is the number of squares that fit in the shape. A rectangle 5 squares long and 4 wide has 4 rows of 5 squares: 5 + 5 + 5 + 5 = 20 squares.
Worked examples
One shape has 12 squares and another has 9: the first has the greater area by 3 squares.
8 red and 6 yellow tiles were stuck on a wall: its area is 14 tiles.
Class activity
“Which is bigger?”: children draw two shapes on squared paper, count the squares and say which has the larger area. Try also shapes with the same perimeter but different areas.
Practice
1
A rectangle is 5 squares long and 4 squares wide. What is its area in squares?
20
2
One shape covers 12 squares and another covers 9. By how many squares is the first one bigger?
3
3
A mosaic has 150 blue pieces, 40 fewer green pieces and 25 more white pieces than blue. How many pieces in total?
435
4
Which shape has the larger area: the 20-square one or the 18-square one?
The 20-square shape
5
Are perimeter and area the same thing?
No: perimeter is the sum of the sides, area is the space covered