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Question
The following figure shows a square cardboard ABCD of side 28 cm. Four identical circles of the largest possible sizes are cut from this card as shown below.
Find the area of the remaining card-board.
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Solution
Area of the square is given by
A = 282
= 784 cm2
Since there are four identical circles inside the square.
Hence the radius of each circle is one-fourth of the side of the square.
Area of one circle = π x 72
= 154 cm2
Area of four circle = 4 x 154cm2
= 616 cm2
Area remaining = 784 - 616
= 168 cm2
The area remaining in the cardboard is = 168 cm2.
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