Lesson 13 — Activity 1: Converting Imperial to Metric


Getting Ready


You learned previously that even though Canada adopted the metric system of measurement, we continue to use both the metric and imperial systems in our everyday lives.


Distances and speed are usually in metric units, and they are reported in metres and kilometres. However, most vehicle speedometers  show both systems (kilometres per hour and miles per hour — that is because most of the vehicles that are for sale in Canada come from the US).


Our temperatures are usually in Celsius, although many thermostats that are sold in Canada are preset to Fahrenheit by their US manufacturers.



          Courtesy of Pixabay

Think about This:

There are many jobs that will require you to use the two systems and convert units from one system to the next. For example, when it comes to the building trades, measurements in feet and inches are still used widely. This is in part because we receive many construction supplies from US manufacturers.

Courtesy of iStock

Therefore, it is important to know both systems and how to convert one to the other. In the activities that follow, you will learn how to convert between the imperial and metric measurement systems.


Converting from Imperial to Metric

Below you will see a chart of equivalents that can be used when converting from the imperial system to the metric system.

To use the chart, you must first find the conversion factor. Remember from L12 — A2, that the conversion factor is the other unit that has a number different than 1 in front of it. You will use this conversion factor to change the units from imperial to metric.


Courtesy of ADLC

For example, let's say you wanted to convert 75 ounces (imperial unit) to an equivalent amount in grams (metric unit). You would do the following:


Step 1: Look under the heading "Imperial to Metric Equivalents"


Step 2: Find the ounce to gram equivalent: It is 1 oz = 28.38 g. This is the conversion factor.


Step 3: Multiply 75 by 28.38:


               75 x 28.38 = 2,128.5 (which you can round up to 2,129)


Step 4: 75 ounces is equal to 2,129 grams.




Let's try a few more examples.


In a book of patterns, Jan has found a dress she would like to make. The requirements for the dress are 22 feet of material. Let's help Jan convert this amount to metres.



Courtesy of Pixabay

Step 1: Look under the heading "Imperial to Metric Equivalents"


Step 2: Find the feet to metre equivalent: It is 1 ft = .305 m.


Step 3: Multiply 22 by .305:


               22 x .305 = 6.71


Step 4: 22 feet is equal to 6.71 metres.


Here's another example:

On a driving vacation in the US, Joe bought gas often. He found he got about 15 US gallons per tank of gas. Let's help Joe convert this amount to litres.



Courtesy of Pixabay


Step 1: Look under the heading "Imperial to Metric Equivalents"


Step 2: Find the US gallons to litre equivalent: It is 1 US gal = 3.78 l.


Step 3: Multiply 15 by 3.78:


               15 x 3.78 = 56.7


Step 4: 15 US gallons  is equal to 56.7 litres.


Try This:

Do the following conversion on your own.

You have 27 pieces of lumber to build a shed. Each piece is 8 feet long. If you are using a blueprint with metric measurements, you may wish to convert this unit to metres to see if you have the correct amount of lumber. How many metres of lumber do you have?

 (Use a calculator to solve.)


  • First, multiply 27 x 8.
  • Then follow the steps above to convert.

Courtesy of Pixabay

27 x 8 = 216 feet of lumber

Step 1: Look under the heading "Imperial to Metric Equivalents"

Step 2: Find the feet to metre equivalent: It is 1 ft = .305 m.

Step 3: Multiply 216 by .305:

               216 x .305 = 65.88

Step 4: 22 feet  is equal to 65.88 metres.



Self-check!


Try This!

Now answer these questions regarding imperial to metric conversions on your own. Use the chart below.

  You may use a calculator to solve.

Courtesy of ADLC


When you are finished, click on the tabs below to check your answers! 


A customer at the deli counter asked Joe for 10 ounces of ham. Help Joe convert this amount to grams.


Step 1: Look under the heading "Imperial to Metric Equivalents"

Step 2: Find the ounce to gram equivalent: It is 1 oz = 28.38 g. This is the conversion factor.

Step 3: Multiply 10 by 28.38:
               10 x 28.38 = 283.8 (which you can round up to 284)

Step 4: 10 ounces is equal to 284 grams.


Jan is flying from Edmonton to Paris. She learned that the distance she will travel is 4,436 miles. Help Jan convert this distance to kilometres.


Step 1: Look under the heading "Imperial to Metric Equivalents"

Step 2: Find the miles to kilometres equivalent: It is 1 mi = 1.6 km. This is the conversion factor.

Step 3: Multiply 4,436 by 1.6:
               4,436 x 1.6 = 7097.6 (which you can round to 7098)

Step 4: 4,436 miles is equal to 7098 kilometres.






Temperature

In L2 — A1, you practised reading the integers on a thermometer.

As noted above, many thermostats and thermometers that are sold in Canada are preset to Fahrenheit by their US manufacturers.  Let's look at how to convert Fahrenheit (an imperial measure) to Celsius (a metric measure).

The image of the thermostat in the Getting Ready section above reads 70 °F. To convert that temperature to Celsius, you would do the following:


Step 1: Look under the heading "Imperial to Metric Equivalents"


Step 2: Find the Fahrenheit to Celsius equivalent: It is (F – 32) x 5/9 = C


Step 3: Rewrite the formula: (70 – 32) x 5/9 = 21.1


Step 4: 70 °F  is equal to 21.1 °C


Try This:


Following the steps above, convert 85 °F to Celsius.


Step 1: Look under the heading "Imperial to Metric Equivalents"

Step 2: Find the Fahrenheit to Celsius equivalent: It is (F – 32) x 5/9 = C

Step 3: Rewrite the formula: (85 – 32) x 5/9 = 29.4

Step 4: 85 °F  is equal to 29.4 °C