Q11 of 35 Page 230

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.

It can be seen from the figure that each blade of wiper would sweep an area of a sector of 115° in a circle with 25 cm radius


Area of such sector = (115/360) ×π × (25)2


= (115/360) × 22/7 × 25 × 25


= 158125/252 cm2


Area swept by 2 blades = 2 ×158125/252 cm2


= 158125/126 cm2


= 1254.96 cm2


≈ 1255 cm2

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