Grade 3 · Unit 5: Using units of measurement

Mass

Grams and kilograms.

Weighing fish

A hilsa fish can have a mass of about 1 kg. Sellers weigh fish to set the price. We use grams and kilograms for mass.

Reading a scale

Each number is 1 kg. Each small mark is ½ kg. The needle is halfway between 3 and 4. The mass is 3½ kg, or 3500 g.

Grams and kilograms

To change kg to g, multiply by 1000. ½ kg = 500 g. 2½ kg = 2500 g.

Comparing masses

The jackfruit is the heaviest. The hilsa is the lightest. The jackfruit (8 kg) is twice as heavy as the cat (4 kg).

Halfway marks

Use fractions to read scales: halfway between 2 and 3 is 2½. A quarter of the way is ¼; three quarters is ¾. 2½ kg = 2.5 kg = 2500 g.

What I learnt

• I can read scales with different intervals.
• I can convert kg to g.