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.​

Answer 1

Given,

• Radius (r) = 25 cm
• Sector angle (θ) = 115°

Since there are two blades,

The total area of the sector made by wiper,

$= 2 \times ( \frac{θ}{360} ) \times \pi {r}^{2}$

$= 2 \times ( \frac{115}{360} ) \times ( \frac{22}{7} ) \times {25}^{2}$

$= 2 \times \frac{158125}{252} \: \: {cm}^{2}$

$= \frac{158125}{126} \: \: {cm}^{2}$

$= 1254.96 \: \: {cm}^{2}$

Answer 2

Given:-

Each wiper has a blade of length 25 cm sweeping through an angle of 115°.

To Find:-

The total area cleaned at each sweep of the blades.

Solution:-

$⟹\textsf{Total area cleaned by 2 wipers = 2 x area cleaned} \\ ⟹\textsf{2 area of sector with 115°}\\ ⟹\textsf{ 2 x 360° = 2} θ \textsf{ x }\pi \textsf{r 2}\\ ⟹\textsf{2 x 360° 115° x 722 x 250} \\ \textsf{Therefore area cleaned by wipers = } \frac{158125}{126} \: \textsf{cm2 } \\\textsf{= 1254.96}$