Page 47 - Mathematics Coursebook

7.1 Simplifying fractions
4 Length, mass and capacity

!e metric system that is used today Key words

Key words
Key words
Key words
Key words
was developed in France, in the late
18th century, by Antoine Lavoisier. Make sure you learn and
At the time, di"erent countries understand these key words:

used di"erent units for measuring, metric units

which was very confusing. !e length
modern metric system is called the millimetre (mm)
International System of Units (SI) centimetre (cm)
and is now used by about 95% of the metre (m)
world’s population. kilometre (km)
mass
Antoine Lavoisier gram (g)
(1743–1794). kilogram (kg)
Some countries that use the metric system, however, still use some tonne (t)
of their old units as well as the metric units. A good example of this capacity
is the UK and the USA, where miles, not kilometres, are shown on millilitre (ml)
road signs. litre (l)
estimate
scale
division

In everyday life people are o#en measuring and weighing. In many

jobs it is vital that measurements are done accurately.
A chef needs to weigh the ingredients needed in the recipe.
If these measurements are wrong, bread and cakes may not rise or
the food may not taste very nice.

An athletics track must be measured accurately.
One circuit of the running track must be exactly 400 m. !e length

of the sprint track must be exactly 100 m.
New world, Olympic or national records can only be set if
distances are accurately measured.
In this unit you will learn more about reading scales on measuring
instruments and using metric measurements.

46 4 Length, mass and capacity 4 Length, mass and capacity