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A steel wire when bent is the form of square encloses an area of 12 cm2. If the same wire is bent in form of circle. Find the area of circle.
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Let side of square = s and length of wire be l. As wire is bent into square
l = perimeter of square = 4s.
Area of square = 121cm2 = s2.
S = `sqrt(121)` = 11ЁЭСРЁЭСЪ
∴ length of wire l = 4(11) = 44cm
As wire is bent into circle (let radius be r)
Length of wire = circumference
44 = 2ЁЭЬЛr
`22/7 × 2 × r= 44 ⇒ r = (44×7)/(2×22) = 7`ЁЭСРЁЭСЪ
ЁЭР┤ЁЭСЯЁЭСТЁЭСО ЁЭСЬЁЭСУ ЁЭСРЁЭСЦЁЭСЯЁЭСРЁЭСЩЁЭСТ = ЁЭЬЛЁЭСЯ2
=` 22/7` × 7 × 7
= 22 × 7
= 154ЁЭСРЁЭСЪ2
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