Goal:
Goal:
Goal: Use subtraction to compare the size of different objects.
Let’s use subtraction to compare the length of a pencil and a crayon! You will need a crayon, a pencil, a ruler, and a meter stick.
Hands-On
Which form of measurement should we use to measure the pencil and crayon?
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Centimeters
Meters
The pencil and crayon are less than a meter, so we will use centimeters to measure them.
Both the pencil and crayon fit within the ruler, so let’s use the ruler to measure them!
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How long is the pencil?
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This pencil is 18 centimeters long. How long is your pencil?
How long is the crayon?
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This crayon is 8 centimeters long. How long is your crayon?
You can compare the length of your pencil and crayon by subtracting their lengths.
pencil - crayon = ___
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This pencil is 10 centimeters longer than the crayon because 18 - 8 = 10. How much longer is your pencil than your crayon?
How much longer is the microphone than the headphones?
29 - 20 = ___
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Correct! The microphone is 9 centimeters longer than the headphones because 29 - 20 = 9.
The microphone is 9 centimeters longer than the headphones because 29 - 20 = 9.
Click the button below to download your worksheet.
Compare Metric Lengths