Question

the diameter of the wheel of a car is70cm. how many revolutions will it make to travel 1.65km?

Answer 1

The circumference of a circle is Pi x Diameter

C = Pi x D

C = 3.14 x 70cm

C = 220cm

Next convert 220cm to km = 220 / 100000 = 0.0022 km

1.65km / 0.0022km = 750 revolutions

Answer 2

Given diameter = 70cm.Then the radius will be r = d/2 = 35cm.

We know that circumference = 2 * pi * r

                                                 = 2 * (22/7) * 35

                                                 = 220 cm

Given target = 1.65km = 1.65 * 10000

                                      = 165000 cm.

If  220 cm = 1 revolution

Then 165000 =?

= 165000/220

= 750.

It will make 750 revolutions.