Question

how many rotations do a wheel take to cover a distance of 1.32 kilometre if the radius of the wheel is 21 centimetre

Answer 1

We'll divide the distance covered by the circumference of the wheel to get the no. of rotations 

Circumference of the wheel -  (2 X 22/7 X 21) cm
                                              =132 cm = 0.00132 km

                Distance covered -  1.32 km

                   No. of rotations -  1.32 / 0.00132
                                              =1000