question_answer

                        The circumference of a circle is 31.4 cm. Find the radius and the area of the circle. (Take\[\pi =31.4\])

Answer:

Let the radius of the circle be r. Then, Circumference = 31.4cm or  \[2\pi =31.4\] or, \[2\times 3.14\times r=31.4\] Or  \[r=\frac{31.4}{2\times 3.14}=5\]                                                                                                                  \[\therefore \] Radius = 5 cm                                Area of the circle = \[\pi {{r}^{2}}\]= (\[3.14\times 25\]) \[c{{m}^{2}}\] = 78.5\[c{{m}^{2}}\]