Reading a dial scale

In your book, Maths Mela (Chapter 8), there are six dial weighing scales to read. A dial scale has a round face with marks around it and a pointer in the middle. When something is put on the scale, the pointer turns round from 0, and the mark it stops at tells the weight.

The dials in your book do not all go up to the same weight. Some go up to 1 kg, some to 2 kg, some to 4 kg and some to 6 kg. On every one of them, 0 is at the very top. The biggest weight is at the top too, in the same place as 0, because the pointer goes all the way round to get back there. On a 4 kg dial, 1 kg, 2 kg and 3 kg are spaced out round the face, and the top mark is both 0 and 4 kg. On a 2 kg dial, 1 kg is at the very bottom, halfway round.

Between the numbered marks there are small marks. Before you read a dial, work out what each small mark stands for. Count the equal spaces between two numbered marks and share out the weight between them. On a 4 kg dial, the gap from 1 kg to 2 kg is 1 kg = 1,000 g. If that gap has 4 equal spaces, each space is 250 g, because 4 × 250 g = 1,000 g.

On a 1 kg dial the numbered marks are 0, 250 g, 500 g and 750 g, and 1 kg is back at the top. If there are 5 equal spaces between 250 g and 500 g, each space stands for 50 g, because 5 × 50 g = 250 g.

Then read the dial: find the last numbered mark the pointer has passed, and add the small spaces after it. If the pointer is exactly halfway between two numbered marks, the weight is halfway between them too.