Question

The wheels of a car make 2500 revolutions in covering a distance of 4.95 km. Find the diameter of a wheel.

Answer 1

Distance $=4.95km=4.95\times 1000\times 100cm$

Therefore, Distance covered by the wheels in 1 revolution $=\frac{\text{Total distance covered}}{\text{Number of revolutions}}=\frac{4.95\times 1000\times 100}{2500}=198cm$

Now,

The circumference of the wheel = 198 cm

$\Rightarrow 2\pi r=198\Rightarrow 2\times \frac{22}{7}\times r=198\Rightarrow r=198\times \frac{7}{44}=31.5cm$

Therefore, Diameter of the wheel $=2r=2\left(31.5\right)=63$ cm