Measurement, maps and scale

WJEC Foundation and Intermediate test practical measuring and scale-reading skills.

Measuring line segments

• Use a ruler in mm where possible; one decimal place in cm is sufficient.
• Measure between marks/points carefully.
• WJEC tolerance: ±2 mm on a printed paper; ±1° on angles.

Measuring angles

• Use a protractor with the centre on the vertex and the zero line along one arm.
• Read the inner or outer scale according to the direction.
• Acute, obtuse, reflex, right — classify before reading. If you see an obtuse angle but read 45°, you read the wrong scale.

Scale notation

• 1 : 50 means 1 unit on the drawing represents 50 of the same unit in real life.
• 1 cm : 5 m means 1 cm on the drawing = 5 m in reality. Equivalent ratio: 1 : 500 (since 5 m = 500 cm).

Converting drawing → real

Multiply by the scale factor.

• Drawing 6 cm at 1 : 200 → 6 × 200 = 1200 cm = 12 m in real life.

Converting real → drawing

Divide by the scale factor.

• 8 m at 1 : 200 → 800 ÷ 200 = 4 cm on the drawing.

Bearings

Bearings are angles measured CLOCKWISE from north. Always 3 digits: 045°, 130°, 270°.

Map reading

• Compute distance: measure on the map, multiply by scale.
• Compute bearing: align north, measure clockwise from N to the line.

Scale drawings — practical exam pattern

WJEC asks candidates to draw an accurate scale plan from given measurements.

• Choose a scale that fits the page.
• Construct using ruler + protractor + compasses.
• Annotate with all real measurements and the scale used.

WJEC exam tip

When asked for a real-world distance from a printed map, write the SCALE EQUATION first ("1 cm represents 25 m") then your measurement, then the multiplication. The scale statement is a B1 mark in its own right.