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Question
The area of the circle is 154 cm2. The radius of the circle is ______.
Options
7 cm
14 cm
3.5 cm
17.5 cm
Solution
The area of the circle is 154 cm2. The radius of the circle is 7 cm.
Explanation:
Area of circle = 154 cm2
`=> pi "r"^2 = 154 "cm"^2`
`=> 22/7 xx "r"^2 = 154`
`=> "r"^2 = 154 xx 22/7`
`=> "r"^2 = 7 xx 7 = 49`
`therefore "r" = sqrt49 = 7`
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