**Q) **A car has two wipers which do not overlap. Each wiper has a blade of length 21 cm sweeping through an angle of 120°. Find the total area cleaned at each sweep of the two blades.

**Ans:**

Area cleaned by a blade = π r^{2}

= x 21 x 21 x

= x 21 x 21 x

= 22 x 21

= 462 cm^{2}

The area cleaned by 2 blades:

= 462 x 2

= 924 cm^{2}

**Therefore, the area cleaned by two blades = 924 cm ^{2}**