Mathematics
If the radius of a circle is doubled, then its area will become :
doubled
halved
four times
three times
Mensuration
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Answer
Let r be the radius of circle.
Area of circle = πr2
When the radius is doubled, new radius = 2r
Area of new circle = π x (2r)2
= π x 4r2
= 4πr2
The new area is four times the area of the original circle.
Hence, option 3 is the correct option.
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