MSS1/L2.6 Calculate with units of measure between systems, using conversion tables and scales, and approximate conversion factors
(a) know rough equivalencies between common metric and imperial measures, e.g. 1lb is about 450 grams, a litre is a bit less than 2 pints, a gallon is about 4.5 litres, a kilogram is a bit more than 2lb, a metre is a bit more than a yard, an inch is about 2.5 cm, a foot is about 30 cm.
(b) know how to read conversion scales and tables
(c) know how to use approximate conversion factors, e.g. 1 inch = 2.54 cm