23/09/2026
In Mathematical Literacy, you will often work with measurements such as length, mass, capacity, temperature, area and volume. There are two major systems of measurement you may encounter: the *metric system* and the *imperial system*.
1. What is the Metric System?
The *metric system* is a measurement system based mainly on powers of 10. This makes converting between units relatively easy because you usually multiply or divide by 10, 100,
1 000, etc.
The *metric system* is used in South Africa and most countries around the world.
Examples of metric units
-Length
Millimetre (mm)
Centimetre (cm)
Metre (m)
Kilometre (km)
Example:
* 1 metre = 100 centimetres
* 1 centimetre = 10 millimetres
* 1 kilometre = 1 000 metres
So, if a road is 5 km long:
5 km =5×1 000
=5 000 m
2. What is the Imperial System?
*The imperial system* uses units such as inches, feet, yards, miles, ounces and pounds.
It is different from the *metric system* because its conversions are not generally based on powers of 10.
Examples of imperial units
-Length
Inch (in)
Foot (ft)
Yard (yd)
Mile (mi)
Some important relationships are:
12 inches = 1 foot
3 feet = 1 yard
1 760 yards = 1 mile
For example:
5 feet = 5 × 12
= 60 inches
3. Main Difference Between the Two Systems
The biggest difference is the units used and the way conversions are made.
Metric
Metric conversions are usually based on 10.
For example:
1 m = 100 cm
1 km = 1 000 m
Imperial
Imperial conversions use different fixed numbers.
For example:
1 foot = 12 inches
1 yard = 3 feet
1 mile = 1 760 yards
So, metric conversions are generally easier to calculate because they follow a decimal system.
4. Length
Length tells us how long, wide, tall or far something is.
Metric length units
Unit Meaning
mm- millimetre
cm - centimetre
m -metre
km- kilometre
Example:
-A pencil could be approximately 15 cm long.
-A classroom could be approximately 8 m long.
The distance between two towns could be 25 km.
Imperial length units
Unit Meaning
inch (in) small length
foot (ft) 12 inches
yard (yd) 3 feet
mile (mi) long distance
Example:
A person's height might be given as 5 feet 8 inches in an imperial measurement.
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5. Mass/Weight
Mass tells us how much matter an object contains, while everyday language often uses the word "weight."
Metric
Common units are:
milligram (mg)
gram (g)
kilogram (kg)
tonne (t)
Examples:
1 kg = 1 000 g
A packet of sugar may weigh 2 kg.
A small medicine tablet might have a mass of 500 mg.
Imperial
Common units include:
ounce (oz)
pound (lb)
stone (st)
Examples:
16 ounces = 1 pound
14 pounds = 1 stone
So, if something weighs 3 pounds, that is:
3 × 16 = 48 ounces
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6. Capacity/Volume
Capacity tells us how much liquid a container can hold.
Metric
Common units:
millilitre (mL)
litre (L)
Important conversions:
1 L = 1 000 mL
Example:
A bottle contains 1.5 L of water.
Convert to millilitres:
1.5 × 1 000 = 1 500 mL
Therefore:
1.5 L = 1 500 mL
Imperial
Common units include:
fluid ounce
pint
gallon
For example, fuel may be measured in gallons in countries that use imperial/US customary measurements.
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7. Temperature
Temperature tells us how hot or cold something is.
The metric system commonly uses:
Celsius (°C)
Examples:
Water freezes at 0°C
Water boils at approximately 100°C at standard atmospheric pressure.
A hot summer day might be around 30°C.
The imperial/US customary system commonly uses:
Fahrenheit (°F)
For example:
Water freezes at 32°F
Water boils at 212°F at standard atmospheric pressure.
The conversion formulas are:
°F = (°C × 9/5) + 32
°C = (°F − 32) × 5/9
Example:
Convert 20°C to Fahrenheit:
(20 × 9/5) + 32
= 36 + 32
= 68°F
8. Metric vs Imperial — Quick Comparison
Measurement Metric Imperial
Small length
millimetre inch
Length centimetre/metre foot/yard
Long distance kilometre mile
Small mass gram ounce
Larger mass kilogram pound
Liquid millilitre/litre fluid ounce/pint/gallon
Temperature Celsius Fahrenheit
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9. Examples You May See in Mathematical Literacy
Example 1: Length
A piece of wood is 2 m long.
Convert to centimetres:
2 × 100 = 200 cm
Therefore:
2 m = 200 cm
Example 2: Mass
A bag weighs 4 kg.
Convert to grams:
4 × 1 000 = 4 000 g
Therefore:
4 kg = 4 000 g
Example 3: Capacity
A container holds 3 L.
Convert to millilitres:
3 × 1 000 = 3 000 mL
Therefore:
3 L = 3 000 mL
Example 4: Imperial length
A person's height is 6 feet.
Since:
1 foot = 12 inches
Then:
6 × 12 = 72 inches
Therefore:
6 feet = 72 inches
10. Why This Is Important in Mathematical Literacy
You need to be able to identify the unit, understand what it measures, and convert it when necessary.
For example, a question may give you:
A road is 3 km long. Calculate the distance in metres.
You must know:
1 km = 1 000 m
Therefore:
3 km = 3 000 m
Remember this rule:
When converting metric units, check whether you are moving to a smaller or larger unit.
Larger unit → smaller unit: multiply
Smaller unit → larger unit: divide
For example:
5 km → m: multiply by 1 000
5 000 m → km: divide by 1 000
This is one of the important foundations you should understand before starting Measurement in Grade 12 Mathematical Literacy Paper 2.
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