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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

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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.

Sum
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Solution

Area of the square is given by

A = 282
   = 784 cm

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 7 
                             = 154 cm2

Area of four circle = 4 x 154cm 
                             = 616 cm

Area remaining = 784 - 616
                          = 168 cm

The area remaining in the cardboard is = 168 cm2.

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Chapter 20: Area and Perimeter of Plane Figures - Exercise 20 (C) [Page 262]

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Selina Concise Mathematics [English] Class 9 ICSE
Chapter 20 Area and Perimeter of Plane Figures
Exercise 20 (C) | Q 9 | Page 262

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