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The Diameters of Two Circles Are 32 Cm and 24 Cm. Find the Radius of the Circle Having Its Area Equal to the Sum of the Areas of the Two Given Circles - Mathematics

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प्रश्न

The diameters of two circles are 32 cm and 24 cm. Find the radius of the circle having its area equal to the sum of the areas of the two given circles.

योग

उत्तर

Let the area of the resulting circle be r.

π x (16)2 + π x ( 12 )2 = π x r2

             256 π + 144 π = π x r2

                          400π = π x r2

                               r2 = 400

                                r = 20 cm

Hence the radius of the resulting circle is 20cm.

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अध्याय 20: Area and Perimeter of Plane Figures - Exercise 20 (C) [पृष्ठ २६१]

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सेलिना Concise Mathematics [English] Class 9 ICSE
अध्याय 20 Area and Perimeter of Plane Figures
Exercise 20 (C) | Q 6 | पृष्ठ २६१

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