Question

the diameter of the wheel of a car is 70 cm how many revolutions will it make to travel 1.65 km

Answer 1

.65 km = 1.65 ×1000×100 cm
              = 165000 cm 
now,radius = diameter/2
           = 70/2
           =35 cm
now, circumference = 2π r
                                 = 2×(22/7)×35
                                 = 220 cm
it means, 220 cm = 1 revolution
       then, 165000 cm = 165000/220
                                   = 750 revolution