Page 191 - SK Year 5 Mathematics DLP

SUBTRACTION OF UNITS OF LENGTH

1 a What is the difference in height 62.7 cm 3 cm
between Robot R and Robot S? 54.9 cm 5
shorter
62.7 cm – 54.9 cm = cm
than
11
5 1 17 Robot S
62.7 cm
– 54.9 cm
7.8 cm R S T

62.7 cm – 54.9 cm = 7.8 cm
The difference in height between Robot R and Robot S is 7.8 cm.

b Calculate the height, in mm, of Robot T.
3
54.9 cm – cm = mm
5
3 3 2
54.9 cm – cm = (54.9 × 10) mm – ( × 10) mm
5 5
= 549 mm – 6 mm 1
= 543 mm
3
54.9 cm – cm = 543 mm
5
The height of Robot T is 543 mm.

4
2 2.07 m – 16 cm – m = m
5
First, convert the measurement in
16 cm = (16 ÷ 100) m 0.8 m decimal m. Then, subtract.
5 4.0 m
= 0.16 m
−0 1 10
4 0 2. 0 7 m
−4 0 – 0. 1 6 m
0
1 . 9 1 m
– 0. 8 0 m
4 1 . 1 1 m
2.07 m – 16 cm – m = 1.11 m
5

• Encourage pupils to subtract by finding the balance or difference
of length of an object. 183
5.1.4
• Ask pupils to carry out the required conversion of unit of length
according to the questions.