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Units of area
Textbook: Part 3, lesson 83, pp. 24–25
GoalUnits of area: cm², dm², m² and how they are linked.
New words
square centimetre · kvadrat santimetrsquare decimetre · kvadrat detsimetrsquare metre · kvadrat metrunit of area · yuz birligi
Explanation
Area is measured in square units. A square with side 1 cm has area 1 cm², with side 1 dm area 1 dm², and with side 1 m area 1 m². Since 1 dm = 10 cm, 1 dm² holds 10 rows of 10 cm²: 1 dm² = 100 cm². In the same way 1 m² = 100 dm².
Worked examples
3 dm² = 300 cm², 700 cm² = 7 dm².
5 dm² 17 cm² = 500 cm² + 17 cm² = 517 cm².
Class activity
“Make 1 dm²”: children cut a square with side 1 dm, divide it into 1 cm squares and count how many there are.
Practice
1
8 m² = ? dm²
800
2
3 dm² = ? cm²
300
3
600 cm² = ? dm²
6
4
7 m² 63 dm² = ? dm²
763
5
345 cm² + 278 cm² = ? cm²
623