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Question
A wire can be bent in the form of a circle of radius 56 cm. If it is bent in the form fo a square, then its area will be
Options
3520 cm2
6400 cm2
7744 cm2
8800 cm2
Solution
We have given that a wire is bent in the form of circle of radius 56 cm. If we bent the same wire in the form of square of side a cm, the perimeter of the wire will not change.
∴ perimeter of the circle = perimeter of the square
`∴ 2pi r=4a`
We know that r = 56 cm.
Now we will substitute the value of r in the equation,
`2xxpixx56=4a`............(1)
`∴ 2xx22/7xx56=4a`
`∴2xx22xx8=4a`
Dividing both sides of the equation by 4 we get,
`∴ a=(2xx22xx8)/4`
`∴ a=2xx22xx2`
`∴ a=88`
Now we obtained side of the square. Now we can calculate the area of the square as given below.
Area of the square=`a^2`
Area of the square=`88 ^2`
Area of the square=`7744`
Hence, the area of the square is `7744 cm^2`
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