Converting Between Systems of Measurement: Imperial and SI-Units

Converting Between Systems of Measurement

If you memorize the most common conversion rates, you will be able to convert between most SI units and imperial units. (You can use Flashbulb to create flashcards that will help you memorize these rates.)

Some commonly used conversions are listed below. Each example shows the # of smaller units in one of the larger units.

Length

 Imperial SI 1 mile 1.6 km 3.3 feet 1 meter 1 inch 2.54 cm

Volume

 Imperial Metric 1 gallon 3.79 liters 1 fluid oz. 30 ml

Weight

 Imperial Metric 1.102 net, or short tons (2,000 pounds) 1 metric ton (1,000 kg) 2.2 pounds 1 kilogram 1 ounce 28.35 grams

Do you ever really have to do this?

…Here are a few scenarios when you’d need to use this skill:

Length

Customary to Metric

1. The American tour guide said that the stuntmen, who went over Horseshoe Falls in a barrel, fell 167 feet. On the other side of the river, the Canadian tour guide said that stuntmen fell ______ meters

Approximately how many meters did they fall?

(Some fell to their death, so it's best not to repeat the stunt!)

Metric to Customary

A runner is training for a 10-kilometer race. How many miles will she be running?

Volume

Customary to Metric

The pastry chef bought a gallon of milk and needed to use 1 liter for a wedding cake. How many liters of milk would she have left after baking the cake?

Metric to Customary

A mother and son decided to do a chemistry experiment in their kitchen. It called for 100 mL of vinegar, but they only had a measuring cup. What fraction of a cup would that be? (1 cup = 237 ml)

Weight

Metric to Customary

If a European company ordered 1,000 kg of coal, how many pounds of coal would that be?

Customary to Metric

The elephant at the zoo weighs 24,000 pounds. Since Elsie is making a brochure for foreign tourists, she needs to add the equivalent weight in kilograms. How much does the elephant weigh in kilograms?

Metric to Customary

Silver was valued at \$43.80 per oz. If the customer had 50 grams of silver in her jewelry box, how many ounces would that be? And what would be its value?

Customary to Metric

Grams to ounces: Adults under 51 should limit their sodium intake to 2,300 milligrams per day. How many ounces of sodium is that equivalent to?

The Exception!

Temperature. You need to use equations to convert Fahrenheit to Celsius:

EXAMPLE

Should the tourist wear a sweater if it'll be 30 degrees Celsius in Paris?

SOLUTION

Use one of the equations to convert Celsius to Fahrenheit:

The tourist would not need the sweater in this case—it will be hot!

Math Challenge (Area)

Convert square feet to square meters

Anne stayed at a guestroom in Europe that was 12 square meters. If her studio apartment in America is 150 square feet, approximately how many square feet larger is her room in America?