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Question
- Find the length of the boundary of square D.
- 8 squares of side 1 cm are cut out of the square D. Now it looks like shape E. What is the length of the boundary of shape E?
- The boundary of this
is ______ + ______ + ______ + ______
Can we also say that the boundary is 4 × 1 cm?
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Solution
- The boundary of shape D = 5 cm + 5 cm + 5 cm + 5 cm = 20 cm
- There are 21 edges measuring 1 cm of shape ‘E’.
Hence, the boundary of shape ‘E’ = 1 cm x 21 = 21 cm - The boundary = 1 cm + 1 cm + 1 cm + 1 cm = 4 cm
So, we can say the boundary of = 4 × 1 cm.
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