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A rectangle has a perimeter of 60 cm. It's length is 21 cm. What is its width (w)?

User JBirdVegas
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2 Answers

4 votes
Okay so we know the length is 21. But with perimeter, we have two lengths. So 21+21 is 42. Then subtract 42 from 60, which is 18. Then, since we know there are two widths, divide 18 by 2. This gives you 9. 9cm
User Hadimbj
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7 votes
It’s width is 9cm.

We use the formula P = 2(l + w) in which the formula goes as:

w= p/2 - l= 60/2 - 21

= 9cm!

User NakedCat
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