Question

The diameter of wheel car is 77 cm. How many revolutions will it make to travel 100 km

Answer 1

Answer:

you need to find it circumference..

then divide the distance by circumference..

dnt forget to make the both unit same

Answer 2

SOLUTION :

The diameter of the wheel of car = 77 cm   (given)

To be found :

The number of revolution the car will make to travel 121 km

radius of the wheel = 77 ÷ 2 = 38.5 cm   [ as radius = diameter ÷ 2 ]

1 revolution of the wheel = 1 circumference of the wheel

So,

Circumference of the wheel = 2πr  units

                                              = 2 × 22/7 × 38.5  cm

                                              = 242 cm

242 cm = 0.00242 km   [ ∴ As 1 km = 100000 cm ]

If the wheel makes 1 revolution to covers 0.00242 km

So,

The number of revolution the wheel will make to cover 121 km is

=

= 50000 revolutions

Hence

the wheel of the car will make 50000 revolutions to travel 121 km.