102
How decimetres and centimetres relate
Textbook Part 3, pp. 58–59
GoalConvert centimetres to decimetres and centimetres and back; read data from a table.
New words
to convert · aylantirmoqheight (of a person) · bo‘yaverage · o‘rtacha
Explanation
Centimetres and decimetres work like ones and tens: 48 = 4 tens 8 ones, and in the same way 48 cm = 4 dm 8 cm. The other way: 6 dm 2 cm = 60 cm + 2 cm = 62 cm.
Worked examples
An adult’s heart beats 70 times a minute and a child’s 80 times: 80 − 70 = 10 times more.
93 cm = 9 dm 3 cm
Class activity
Height chart: children measure each other on a wall chart and write it as “… dm … cm” (e.g. 12 dm 3 cm).
Practice
1
57 cm = ? dm ? cm
5 dm 7 cm
2
8 dm 1 cm = ? cm
81 cm
3
Pattern: 10 cm, 20 cm, 30 cm, _
40 cm
4
Table: a 2-year-old is 85 cm tall and a 3-year-old 95 cm. Difference?
10 cm