A car has two wipers which do not overlap. Each wiper has a blade of length $25\text{ cm}$ sweeping through an angle of $115^\circ$. Total area cleaned at each sweep of the blades is:
(a) $\dfrac{158125}{126}\text{ cm}^2$
(b) $\dfrac{158125}{252}\text{ cm}^2$
(c) $1254.96\text{ cm}^2$
(d) $\dfrac{158125}{63}\text{ cm}^2$
Step-by-Step Solution
Key Concept: Total area $= 2 \times \dfrac{115}{360} \times \dfrac{22}{7} \times 625 = 2 \times \dfrac{23}{72} \times \dfrac{22}{7} \times 625 = \dfrac{158125}{126}\text{ cm}^2$.
$\text{Total Area} = 2 \times \dfrac{23}{72} \times \dfrac{22}{7} \times 625 = \dfrac{158125}{126}\text{ cm}^2$. [1.0 Mark]
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Calculating total cleaned area $= 158125/126\text{ cm}^2$: 1.0 Mark
Correct Answer: $\dfrac{158125}{126}\text{ cm}^2$