Converting compound units

Changing m/s into km/h by converting numerator and denominator separately.

Compound units with a squared or cubed part

Converting grams per cubic centimetre to kilograms per cubic metre.

Reading scales

What one division is worth on a ruler, jug, dial or weighing scale.

Choosing a sensible unit

Picking the unit that fits the quantity, so a door is measured in metres.

Estimating everyday measurements

Estimating a length, mass or capacity against a quantity you already know.