Standard Measurement

When measuring, it is sometimes necessary to change from one unit into another.

Unit refers to what you are measuring.

Miles / yards / feet / inches = units of distanceTons / pounds / ounces = units of weightGallon / quarts / pints / cups = units of amount

FOR EXAMPLE…

Standard Measurement

When changing from one unit to another, you have to do a process called…

CONVERSION.

Conversion means using conversion factors, or equalities, to multiply and divide our originally measured units and turn them into different units.

Standard Measurement

An equality is any two amounts (and units) that appear different, but are actually the same value.

For example…

1 foot = 12 inches

1 ≠ 12

Feet ≠ inches

1 foot does equal 12 inches.

Standard Measurement

Other examples of conversion factors (equalities) would also be…

1 year = 365 days (or 1 year = 12 months)

1 chess board = 64 squares

206 bones = 1 human body

2 pair of Aces = Four of a kind

Let’s say our problem is…

4 gallons (gal) = ___ cups (c)?

“How many dishes of ice cream we can make from 4 gallons, if each dish is one cup?”

Standard Measurement

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

1) First, make a copy of this chart, making sure to shade the lower, left-hand space as shown…

4 gallons (gal) = ___ cups (c)?

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

2) Put the known quantity from your problem in the upper, left-hand space, as follows…

4 gallons (gal) = ___ cups (c)?

4 gal

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

3) Choose an equality that contains the units you already know.

4 gallons (gal) = ___ cups (c)?

4 gal

1 gal = 4 qt

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

3) Place half the equality in the bottom box and the other half in the top box.

4 gallons (gal) = ___ cups (c)?

4 gal

HINT: the half on the bottom should be the half that has the same units as the known amount.

4 qt

1 gal

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

4) Cross out the units that are similar on the top and bottom, as follows…

4 gallons (gal) = ___ cups (c)?

4 gal 4 qt

1 gal

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

5) Now check – is the remaining uncrossed unit the unit we are looking for?

NO

4 gallons (gal) = ___ cups (c)?

4 gal 4 qt

1 gal

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

If the answer is “YES”… - we go to step #6

If the answer is “NO”… - we go back to step #3 - we add another conversion factor

4 gallons (gal) = ___ cups (c)?

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

4 gallons (gal) = ___ cups (c)?

4 gal 4 qt

1 gal

2 pt

1 qt

3) Put the correct equality in the next set of boxes to the right. It should also contain the same units as those remaining, and they should be placed in the bottom box again.

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

4) Cross out the units that are similar on the top and bottom, as follows…

4 gallons (gal) = ___ cups (c)?

4 gal 4 qt

1 gal

2 pt

1 qt

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

NO

4 gallons (gal) = ___ cups (c)?

2 pt

1 qt

4 gal 4 qt

1 gal

5) Now check – is the remaining uncrossed unit the unit we are looking for?

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

Step 3 / 4 / 5 again! Put a new equality, and then cross out the units that are similar on the top and bottom…

4 gallons (gal) = ___ cups (c)?

2 c

1 pt

4 gal 4 qt

1 gal

2 pt

1 qt

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

FINALLY! The units we were looking for are in the top row!

4 gallons (gal) = ___ cups (c)?

2 c

1 pt

4 gal 4 qt

1 gal

2 pt

1 qt

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

6a) First, multiply all the numbers on the top row:

4 gallons (gal) = ___ cups (c)?

2 c

1 pt

4 gal 4 qt

1 gal

2 pt

1 qt

4 x 4 x 2 x 2 = 64

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

6b) Then, multiply all the numbers on the bottom row:

4 gallons (gal) = ___ cups (c)?

2 c

1 pt

4 gal 4 qt

1 gal

2 pt

1 qt

1 x 1 x 1 = 1

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

6c) Now, divide the top row’s product by the bottom row’s product:

64= 64

1

4 gallons (gal) = ___ cups (c)?

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

64

1= 64

6c) Don’t forget to put the newnew, correct units!

There are 64 one cup servings in 4 gallons.

cups

4 gallons (gal) = ___ cups (c)?

Standard Measurement

In order to convert (change) one unit to another, you need to do the following steps…

6d) If necessary, round your answer to the nearest

HUNDREDTHS

8 516

483

.

.000

0

3

2460

7

5640

5

40

6.38rounded =

51

8for example…

0