Multiple choice

The diameter of a solid right circular cone is 14 metres and its slant height is 12 metres. Find the cost of colouring its total surface at the rate of 14 paise per sq. metre.

  1. Rs. 55.50

  2. Rs. 60.02

  3. Rs. 58.52

  4. Rs. 60.55

  5. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Diameter = 14, radius r = 7. Slant height l = 12. Total surface area = pi * r * (r + l) = (22/7) * 7 * (7 + 12) = 22 * 19 = 418 sq m. Cost = 418 * 0.14 = 58.52.

AI explanation

Using the formula for the total surface area of a solid right circular cone, we calculate pi * r * (l + r). Substituting the given values gives 22/7 * 7 * (12 + 7), which equals 22 * 19 = 418 square metres. Multiplying this area by the rate of 14 paise per square metre gives 5852 paise. Converting paise to rupees by dividing by 100 gives Rs. 58.52.

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