Reading Scales: Jugs, Rulers & Dials

ME7Reading Scales

Work out what each mark is worth.

Reading a scale means finding the value of each small division first.

What does the arrow show?

0 to 500 g in 10 divisions → each mark = 50 g

Gap value = (big number − small number) ÷ number of gaps.

Learn the 3-Step Method

1Read the labelled numbers.

Find two labelled marks, e.g. 0 and 500.

0 … 500

2Count the gaps between them.

Count GAPS, not marks. Here: 10 gaps.

10 gaps

3Divide to find each gap.

(500 − 0) ÷ 10 = 50. Each mark is worth 50.

500 ÷ 10 = 50

💡 Key IdeaScales on jugs, rulers and weighing scales all work the same way: find the gap value first, then count along.

Worked Example

A measuring jug is labelled 0, 200, 400, 600 ml, with one unlabelled mark between each pair. The juice reaches one mark above 400. How much juice?

Gap value

200 ÷ 2 = 100 ml

2 gaps between labels

→

Count up

400 + 100 = 500

→

✓ Answer

500 ml

Watch Out! Common Mistakes

Counting marks instead of gaps.

The classic! 11 marks make only 10 gaps. Always count the spaces between marks.

Assuming every mark is worth 1.

arrow at 7th mark → “7 g” ✕

Wrong! Find the gap value first — here each mark is 50 g, so the 7th mark is 350 g.

Reading the wrong direction.

Careful with dials! Some scales run right-to-left or curve round. Check which way the numbers grow before reading.

⬇ Cheat Sheet

READING SCALES

Find two labelled numbers.
Count the GAPS between them.
Gap value = difference ÷ gaps.
Count on from a label to the pointer.

Example: 0–500 g with 10 gaps → 50 g per mark → 7th mark = 350 g

📖 Continue Your Journey

✓ ME1 Units of Length ✓ ME2 Converting Length ✓ ME3 Units of Mass ✓ ME4 Converting Mass ✓ ME5 Units of Capacity ✓ ME6 Converting Capacity ME7 Reading Scales ME8 Perimeter ME9 Area of Rectangles ME10 Area of Triangles ME11 Area of Parallelograms ME12 Compound Shapes ME13 Volume of Cuboids ME14 Telling the Time ME15 Time Calculations ME16 Money Calculations ME17 Imperial and Metric Units ME18 Measurement Problem Solving

→

Next Lesson: ME8 PerimeterThe distance all the way round.

📄 Free printable: Download the Reading Scales cheat sheet (PDF) — keep it by your child's desk.

Quick summary

Find two labelled numbers on the scale.
Count the gaps (not the marks) between them.
Gap value = difference ÷ number of gaps.
Count on from the nearest label to the pointer.

Frequently asked questions

How do you read an unlabelled mark on a scale?

Work out what each division is worth — take two labelled numbers, find their difference, and divide by the number of gaps between them. Then count on from a label.

Why do children misread scales?

Almost always by counting marks instead of gaps (11 marks = 10 gaps), or assuming each mark is worth 1. The gap-value routine fixes both.

Where do scale questions appear in exams?

Measuring jugs, weighing scales, thermometers and rulers — usually asking for a value at an unlabelled mark, exactly as practised here.

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ME6 Converting Capacity