question_answer 19)

If the circumference of a circular sheet is 154 m, find its radius. Also find the area of the sheet. \[\left( \text{Take  }\!\!\pi\!\!\text{  = }\frac{\text{22}}{\text{7}} \right)\]

Answer:

                Circumference of the circular sheet = 154 m \[\Rightarrow \]               Radius of the circular sheet (r) \[=\frac{154\times 7}{2\times 22}=\frac{49}{2}\text{m}\] \[\therefore \]  Area of the sheet \[=\pi {{r}^{2}}=\frac{22}{7}{{\left( \frac{49}{2} \right)}^{2}}{{\text{m}}^{\text{2}}}\]                 \[=\frac{22}{7}\times \frac{49}{2}\times \frac{49}{2}\times {{\text{m}}^{\text{2}}}=1886.\text{5 }{{\text{m}}^{\text{2}}}\]