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.

Area swept by each wiper = Area of sector of radius 25 cm and angle 115°.

We know that,

Area of sector of angle θ and radius r = $\dfrac{θ}{360°} \times πr^2$

Substituting values we get :

$\text{Area swept by each wiper} = \dfrac{115°}{360°} \times \dfrac{22}{7} \times 25^2 \\[1em] = \dfrac{23}{72} \times \dfrac{22}{7} \times 625 \\[1em] = \dfrac{23 \times 11 \times 625}{36 \times 7} \\[1em] = \dfrac{158125}{252} \text{ cm}^2.$

Area swept at each sweep of blades = 2 × Area swept by each wiper

= $\dfrac{158125}{252} \times 2 = \dfrac{158125}{126}$ cm².

Hence, area cleaned at each sweep of blades = $\dfrac{158125}{126}$ cm².