WEBVTT
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The table shows the relation between the side lengths of squares and their perimeters.
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Find the values of π, π and π.
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There are two rows in our table.
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The first row shows the side length in centimeters.
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And we know from the first sentence that this is talking about the side length of a square.
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So our three different squares have side length of five centimeters, 10 centimeters, and an unknown amount in the last box.
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This is one of the values we need to find π.
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The second row of our table shows us the perimeter in centimeters for each square.
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The first and second boxes we donβt know.
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We need to find the values of π and π.
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And although we donβt know the side length of the third square, we are told the perimeter, which is four centimeters.
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So our task is to find the values of the three missing numbers π, π, and π.
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Before we start, letβs remind ourselves about squares.
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What do we know about these shapes?
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We know that squares have four sides.
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And importantly, we know that those sides are all equal in length.
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So if we know one side, we can find the perimeter.
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We can see that the first square in the table has a side length of five centimeters.
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And because of the two facts weβve just discussed, squares have four sides and theyβre all equal, we can work out the perimeter.
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So to find the perimeter, we need to multiply five centimeters by four.
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Four fives are 20.
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So we know the perimeter of the first square is 20 centimeters.
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So we can complete the value of π with 20; π equals 20.
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Now, letβs think about the second square mentioned in our table.
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We can see that the side length of our square in centimeters is 10 centimetres.
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So once again, we can use what we know about squares to help us find the perimeter.
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Squares have four equal sides.
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So to find the perimeter of the shape, all we have to do is to multiply 10 centimeters by four.
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We know four times 10 equals 40.
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So we can complete the missing number in this column with the value 40.
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We know π is equal to 40.
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If we look at the final square in our table, we donβt know the side length.
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This is a missing number that we need to find.
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But we do know its perimeter.
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The perimeter of the square is four centimeters.
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We can see that in the bottom box.
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We need to find the value of each side.
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Squares, as we know, have four equal sides. as We keep saying so if we divide four centimeters divided by four, we can find the length of one side.
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Four divided by four equals one centimetre.
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And this is the length of one of our sides.
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This will give us a square with a perimeter of four centimeters.
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We can complete the missing number in our final column with the number one.
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We found the values of π, π and π by applying our knowledge of the properties of squares.
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We know that squares have four sides and theyβre all equal.
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And so we use the side length we were given to help find the perimeters.
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And then we work backwards by using the perimeter we were given to find the side lengths.
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The values of each letter are π equals 20, π equals 40, and π equals one.