A) \[154\,c{{m}^{2}}\]
B) \[77\,c{{m}^{2}}\]
C) \[44\,c{{m}^{2}}\]
D) \[22\,c{{m}^{2}}\]
Correct Answer: A
Solution :
Let a be the side of square. \[{{a}^{2}}=81\] \[\Rightarrow \] \[a=9\,cm\] \[\therefore \] Perimeter of square \[=4\times 9=36\,cm\] \[\therefore \] Length of wire \[=36\] \[\Rightarrow \] \[\pi r+2r=36\] \[r=\frac{36\times 7}{36}=7\,cm\] \[\therefore \] Area of circle \[=\pi {{r}^{2}}\] \[=\frac{22}{7}\times 7\times 7=154\,c{{m}^{2}}\]You need to login to perform this action.
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