Mathematics
Find the circumference of the circle whose area is 16 times the area of the circle with diameter 7 cm.
Mensuration
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Answer
Let area of larger circle be r cm.
Radius of circle with diameter 7 cm = = 3.5 cm.
Given,
Area of larger circle is 16 times the area of the circle with diameter 7 cm.
⇒ πr2 = 16 x π x (3.5)2
⇒ r2 = 196
⇒ r = = 14 cm.
Circumference = 2πr = = 88 cm.
Hence, circumference of circle = 88 cm.
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