Page 168 - Touchpad Mathematics_Ver1.0_C4

example 1. Look at the image below and help the shopkeeper to find the actual weight
of the watermelon.
Solution. The weight on one side of the scale is

2 kg + 5 kg = 7 kg
Weight of the watermelon + 1 kg 1 kg 2 kg

= Weight on the other side of the scale = 7 kg 5 kg
Think of different denominations of weight.
6 kg + 1 kg = 7 kg

Hence, the weight of the watermelon = 7 kg – 1 kg = 6 kg.

example 2. Find the weight of the pumpkin.

Solution. Pumpkin + 500 g = 5 kg + 1 kg 1 kg
Pumpkin + 500 g = 5 kg + 1000 g (Since 1 kg = 1000 g) 500 g 5 kg
Pumpkin + 500 g = 5 kg + 500 g + 500 g
Hence, the weight of the pumpkin is = 5 kg + 500 g = 5 kg 500 g.

Exercise 10C

Find the weight of the objects on the scale.

1. 1 kg 2 kg 2. 2 kg 1 kg
5 kg 5 kg

3. 1 kg 2 kg 5 kg 4. 5 kg 10 kg

500 g 1 kg 500 g
5. 2 kg 6. 1 kg

7. 1 kg 500 g 8. 200 g 500 g
2 kg

166 Mathematics 3