Linear Mesaurement, Area, and Perimeter
Learning Goals for this unit are:
- Estimate, measure, and compare lengths using non-standard units, such as paper clips, straws, or Snap Cube trains.
- Develop an understanding of the need for standard units and measure lengths using the centimetre and the metre.
- Estimate, measure, and compare perimeter (distance around) using non-standard and standard units.
- Investigate area measurements by using non-standard units, such as cards, to cover a surface.
- Solve everyday problems about measurement
How do I measure?
ESTIMATE:
The first step when you measure is to estimate how long you think something is. This will help guide your answer. If you're answer is very far from your estimate, we might have a problem. |
MEASURE:
Now that you have made an estimate, choose your unit of measure (standard or non-standard) and measure your object. |
COMPARE:
Now that you have measured your object, find the difference between your measurement and your estimate. If your measurement is larger, subtract your estimate to find the difference. |
Non-Standard Units of Measure
What is a non-standard unit of measure?
A non-standard unit of measure are not accepted as standard (different the world over) but are used uniformly when measuring (e.g., paperclips, pencils, a tennis shoe, Snap cubes, etc.) There are many possibilites. The reason this is a non-standard unit of measure is because a pencil, eraser, shoe, or any other material may be a different size depending on which you use. If Mr. Pakosh and one of his students were to compare their shoe, whose would be larger? Mr. Pakosh's! So if we measured a desk using our shoes, would we find the same answer? Of course not! |
Standard Units of Measure
A standard unit of measure is a measurement that is universally recognized around the world. The two important standard units of measure you must know are:
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Centimetres vs. Metres
What is a centimetre (cm)?
A centimetre, often written a cm, is a standard unit of measure that is used around the world to measure small objects. 100 cm = 1 m Examples of things we would measure with centimetres:
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What is a metre (m)?
A metre, often written as m. is a standard unit of measure that is used around the world to measure large objects. 1m = 100 cm Examples of things we would measure with metres.
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LEngth and Width
Length: the measurement of something from end to end. The length will be the side which is the longest. Width:the measurement of something from side to side. The width will be the side which is the smallest. Look at the example to your left. It does not matter if length is vertical or horizontal. Rather, you simply must ask the following question: which side is the longest? The answer to that question will be the length! The remaining side will be the width. |
Perimeter
The perimeter is the distance around an object. Let's learn how to find the perimeter of the object. BE CAREFUL! Make sure to know which standard unit of measure you are using.
Perimeter is often shown as 'P'.
How do we find the perimeter?
Perimeter is often shown as 'P'.
How do we find the perimeter?
How would I find the perimeter and show my work using pictures, numbers and words?
Area
The area is the space we measure inside of an object. It is standard to measure the inside using squares with each side either being a centimetre long or a metre long. Therefore, these square centimetres are written down as cm². For square metres, we write m². Area is often shown as A.
YOU MUST WRITE THE "2" ABOVE AND BESIDE THE M! |
How do we find the area of an object?
Simple: If the object is on grid paper, count how many squares are inside of the object. Make sure you check which unit of measurement you are using! Must be cm² or m².
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Advanced: if the object has two pairs of equal sides (as seen below), you can multiply the length by the width. Therefore, L x W = A
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