Lesson 12 — Activity 1: Length

Getting Ready

In L11 — A1, you read a little about the imperial system of measurement.

In this lesson, you will look at it more closely.

"Although the measurements in the metric system are derived from scientific principles, the English units measurements (and the subsequent USA and Imperial measurements) are based on nature and everyday activities.

"For example, a league is based on the distance that can be walked in an hour. Sailors (in days gone by) would drop a weighted rope into the water, lowering it by lengths (where each length was measured by holding the rope between their outstretched hands) until the weight at the end of the rope touched the seabed. This led to the definition of the fathom as the distance from the fingertips of one hand to the fingertips of the other, when the hands are held straight out to the sides. A grain (used to measure small quantities of precious metals) is the weight of a grain of wheat or barleycorn.

"Such natural measures were well suited in a simple agricultural society. However, as trade and commerce grew, it was necessary to have more consistent measures (after all, not all grains of wheat have the same weight and not all sailors have the same length of arm). Consequently, metal weights and lengths were produced to represent exact measures; these metal representations where then used to produce official scales and measurements to ensure that trade was based on standard quantities.

"For larger measures (e.g. a mile) it was impractical to build a metal equivalent, so they were redefined to be multiples of the smaller measures. It is for this reason that the mile was changed in 1595 under Queen Elizabeth I's reign from the Roman standard of 5,000 feet to 5,280 feet (which is 8 furlongs, each furlong equal to 10 chains, each chain equal to 22 yards and each yard equal to 3 feet).

"Despite the development and standardization of the English units of measure, their roots in ancient agriculture and trade have resulted in a diverse and relatively complex set of measurements. The various trades each developed their own measures, so in many cases the measure would depend on what it was being used for: a barrel of oil is not the same size as a barrel of wine (there are in fact eight different barrel sizes officially recognized).

"Likewise there are both fluid ounces and weight ounces, with different types of weight ounces (depending on what was being weighed). This complexity was not eliminated when the English system evolved into the Imperial and USA systems, with the result that these systems have approximately 300 different units of measurement. In comparison, the metric system has only 7 basic units of measurement (which can be increased or decreased in multiples of 10 to make larger or smaller units, or combined to make more complex units)."

From:http: //www.france-property-and-information.com/imperial-system-and-history.htm

Can you see why most countries have switched to the metric system? In this lesson, you will learn about some of the basic imperial measurements that we still use in Canada today.

When you ask someone how tall they are, you are likely to hear them say that they are so many feet and inches tall. If you are a fan of the CFL, you know the field is 110 yards long, and if a team is just short of a first down, the announcer will say they are inches from a first down. A marathon race is 26 miles long. As you can see, even though Canada is a metric country, some imperial measures are still used today.

Unlike the metric system, where every measurement is based on 10, the imperial system does not follow any simple pattern. In this activity, you will learn about inches, feet, yards, and miles and how they are used to measure length.

This football field in Calgary is 110 yards long.


An inch is exactly 2.54 cm long. It is the smallest unit of measure that you will look at in terms of imperial measures of length. You could use inches to say how long and wide a piece of paper is. An inch can be abbreviated as in.

This image shows an inch ruler.


A foot is 12 inches long. It can be used to measure such things as the height of a person or the length of a car. A foot can be abbreviated as ft.

This image shows 12 inches or 1 foot.


A yard is 3 feet long. It is also 36 inches long. A yard is the basic unit of measurement in the imperial system. Inches, feet, and miles all evolved from the yard. A yard can be used to measure such things as the length of a football field. A yard can be abbreviated as yd.

This image shows a yard which is 36 inches long.


A mile is 1,760 yards or 5,280 feet long. It is used to measure great distances. For example, the distance from Edson to Edmonton is 120 miles.

This image shows the route from Edson to Edmonton.
Images courtesy of www.imagesgoogle.com

Digging Deeper

Now that you have looked at the measuring units for length in the metric and imperial systems, click here to try this activity to do some measuring yourself. Play at least one level in both the centimetre and inch categories.