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Unit review: units of mass, area and volume
Textbook: Part 3, pp. 43–44
GoalReview of units of mass, length, area and volume; expressions and diagram problems.
New words
review · takrorlashmass · massaarea · yuzvolume · hajm
Explanation
In mass: 1 kg = 1 000 g, 1 centner = 100 kg, 1 t = 1 000 kg. In length each step is 10 (km to m is 1 000). In area each step changes by 100: 1 m² = 100 dm². In volume each step changes by 1 000: 1 m³ = 1 000 dm³, and 1 dm³ = 1 l. When calculating with mixed units, change everything to the smallest unit.
Worked examples
3 m³ = 3 000 dm³; 15 dm³ = 15 000 cm³; 2 cm³ = 2 000 mm³.
6 dm² 5 cm² + 2 dm² 90 cm² = 605 cm² + 290 cm² = 895 cm² = 8 dm² 95 cm².
Class activity
“Units lotto”: cards show numbers with units (for example 2 m³, 2 000 dm³, 2 000 l). Children find pairs of equal quantities.
Practice
1
4 m³ = ? dm³
4000
2
2 000 cm³ = ? l
2
3
A plot has an area of 3 ha 20 a. How many m² is that?
32000
4
4 t 5 centners − 3 t 2 centners = ? kg
1300
5
(15 400 + 24 600) × 3 = ?
120000