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प्रश्न
Find the diameter of the circle whose area is equal to the sum of the areas of two circles having radii 4 cm and 3 cm.
उत्तर
Let the diameter of the required circle be d.
Now, of the required circle = Are of circle having 4 cm + Area of circle having radius 3 cm
`⇒pi("d"/2)^2=pi(4)^2+pi(3)^2`
`=>("d"/2)^2 = 16 + 9`
`=>("d"/2)^2 = 25 =(5)^2`
`=>"d"/2 = 5`
⇒ d = 10 cm
Hence, the diameter of the circle is 10 cm.
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