A car has two wipers which do not overlap.
Question:

A car has two wipers which do not overlap. Each wiper has a blade of length 25 cm sweeping through an angle of 115°. Find the total area cleaned at each sweep of the blades.

Solution:

Here, one blade of a wipe sweeps a sector area of a circle of radius 25 cm.

The sector angle = 115°

i.e., r = 25 cm

and $\theta=115^{\circ}$

The area covered by one blade

$=\frac{115}{360} \times \pi \times(25)^{2} \mathrm{~cm}^{2}$

Then, the area covered by two blades

$=2 \times \frac{\mathbf{1 1 5}}{\mathbf{3 6 0}} \times \frac{\mathbf{2 2}}{\mathbf{7}} \times 625 \mathrm{~cm}^{2}$

$=\frac{23}{18} \times \frac{11}{7} \times 625 \mathrm{~cm}^{2}$

$=\frac{158125}{126} \mathrm{~cm}^{2}$