 # Introduction to Imperial Units

Lesson You may or may not know that there are two common systems of measurement: the metric system (e.g. metres, litres and kilograms) and the imperial system.

The imperial system was common in the United Kingdom in the mid-nineteenth century and is still used for some measurements. It is also still used in the United States. So let's get familiar with imperial measurements of length, mass and capacity.

## Measurements of Lengths Length of a measure of distance from one point to another. Here are a list of imperial units used to measure length in order from smallest to largest:

• Inch ("): this is a small unit of measurement.
• Foot (ft): $12$12 inches make $1$1 foot. A foot is about as long as a $30$30cm ruler.
• Yard (yd): a yard is equivalent to $3$3 feet. This is about as long as a guitar.
• Mile (mi): this is a large unit of measurement. A mile is $1760$1760 yards and is equivalent to about $2000$2000 steps.

## Measurements of Mass When we weigh something, we are actually measuring its mass. Mass is a measure of how heavy something is, such as a bag of oranges, a suitcase or even a person. Here are a list of imperial measurement units in order from smallest to largest:

• Pound (lb): there are $16$16 ounces in a pound. People are generally weighed in pounds.
• Stone (st): a stone is equivalent to $14$14 pounds. This is not as common but people can be weighed in stones.
• Ton: $2000$2000 pounds equals $1$1 ton. Tons are used to weigh heavy things like cars, trucks and elephants.

## Measurements of Capacity Capacity is a measure of the amount something can contain, for example, how much juice will fit in a bottle. Here are a list of imperial measurement units that relate to capacity in order from smallest to largest:

• Pint (pt): a pint is a relatively small unit of measurement. A small carton of milk is about a pint.
• Quart (qt): a quart is $2$2 pints (or a quarter of a gallon). A large bottle of milk or juice, like the one pictured is about a quart.
• Gallon (gal): a gallon is equivalent to $8$8 pints. The amount of petrol you put in a car is usually measured in gallons.

#### Worked Examples

##### Question 1

Which imperial units would you use to measure these in?

Choose all appropriate options.

1. The length of your kitchen at home.

Inches

A

Yards

B

Gallons

C

Miles

D

Feet

E

Tons

F

Inches

A

Yards

B

Gallons

C

Miles

D

Feet

E

Tons

F
2. The distance from London to New York.

Feet

A

Miles

B

Inches

C

Stones

D

Quarts

E

Yards

F

Feet

A

Miles

B

Inches

C

Stones

D

Quarts

E

Yards

F
3. The length of a pencil.

Yards

A

Inches

B

Miles

C

Feet

D

Pints

E

Ounces

F

Yards

A

Inches

B

Miles

C

Feet

D

Pints

E

Ounces

F

##### QUESTION 2

Complete the sentence, choosing the correct imperial unit for the space.

1. You need $4$4 ________ of flour to make enough biscuits for $6$6 people.

ounces

A

pounds

B

stones

C

tons

D

ounces

A

pounds

B

stones

C

tons

D
2. Tom's mother had a baby this week, she weighs about $7$7 ________.

ounces

A

stone

B

pounds

C

tons

D

ounces

A

stone

B

pounds

C

tons

D
3. Sarah is fifteen years old, she weighs about $8$8 ______.

tons

A

stone

B

pounds

C

ounces

D

tons

A

stone

B

pounds

C

ounces

D

##### QUESTION 3

Complete the sentence, choosing the correct imperial unit(s) for the space.

1. This carton of milk contains 1 _______.

pound

A

gallon

B

ton

C

pint

D

pound

A

gallon

B

ton

C

pint

D
2. David dances a lot. He has to drink about 4 ______ of water every day.

gallons

A

ounces

B

pounds

C

pints

D

gallons

A

ounces

B

pounds

C

pints

D