2016 · Q100
AD is the diameter of a circle with area 707 m² and AB=BC=CD as shown in the figure above.All curves inside the circle are semicircles with their diameters on AD.What is the cost of levelling the shaded region at the rate of ₹ 63 per square metre?
Elementary MathematicsMensuration
- A₹ 29,700
- B₹ 22,400
- C₹ 14,847
- DNone of the above
Explanation
Adding and subtracting the semicircular areas in the figure, the shaded region totals 707/3 m². That is one-third of the whole circle. At Rs 63 per m² the levelling cost is 63 × 707/3 = Rs 14,847, option C.