Page 203 - SK Year 5 Mathematics DLP

May I help you,
MULTIPLICATION OF UNITS OF MASS madam?

1 Calculate the mass of 7 packets of hazelnuts.
7 × 0.25 kg = kg

1 3
0 . 2 5 kg
× 7 kg
1 . 7 5 kg

7 × 0.25 kg = 1.75 kg I want 7 packets of
The mass of 7 packets of hazelnuts is 1.75 kg. hazelnuts.

2 What is the mass of 15 packets of crisps?
1
15 × kg = g
2
1 1 500
15 × kg = 15 × ( × 1 000) g
2 2
1 2
= 15 × 500 g 1 5
× 5 0 0 g
= 7 500 g
1 7 5 0 0 g 1
15 × kg = 7 500 g kg
2 2
The mass of 15 packets of crisps is 7 500 g.

3
3 10 × 40 kg = g
5
Method 1 Method 2

3 3 3 3
40 kg = 40 kg + kg 10 × 40 kg = 10 × (40 kg + kg)
5 5 5 5
3 200 = 10 × (40 kg + 0.6 kg)
= (40 × 1 000) g + ( × 1 000) g
5 = 10 × 40.6 kg
1
= 40 000 g + 600 g = 406 kg

= 40 600 g
406 kg = (406 × 1 000) g
10 × 40 600 g = 406 000 g = 406 000 g

3
10 × 40 kg = 406 000 g
5

• Encourage pupils to do quick calculation when multiplying any 195
5.2.4
mass by 10, 100 or 1 000.