Question

The given figure shows a running track. A boy runs along its edges. Find the distance covered by the boy in one round.

Answer 1

The track consists of a rectangle and two semi-circles.

Let's take the two semi-circles as one circle.

∴The total distance covered = Perimeter of the track

                                               = Length of rectangle + Perimeter of one circle.

Perimeter of the circle = 2πr

                                      = 2 × 22  × 21

                                               -----   ------             (∵ 21 isn't the radius)

                                                 7       2

                                      = 22 × 3

                                      = 66m

∴ Distance covered in 1 round = 60 + 60 + 66

                                            = 186m.