Mensuration Questions

Multiple choice
  1. 16 cm2

  2. 418 cm2

  3. 485 cm2

  4. 16.6 cm2

  5. None of these

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The solid consists of a cylinder (height 19 - 7 = 12cm, radius 3.5cm) and two hemispheres (radius 3.5cm). Surface area = 2 * pi * r * h (cylinder) + 4 * pi * r^2 (sphere) = 2 * pi * 3.5 * 12 + 4 * pi * 3.5^2 = 84pi + 49pi = 133pi = 417.8 approx 418.

Multiple choice
  1. 135.98 kg

  2. 132.59 kg

  3. 133.58 kg

  4. 130.95 kg

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Volume of cylinder = pi * r^2 * h = (22/7) * 7.5^2 * 70 = 12375 cm^3. Volume of hemisphere = (2/3) * pi * r^3 = (2/3) * (22/7) * 7.5^3 = 883.57 cm^3. Total volume = 13258.57 cm^3. Mass = 13258.57 * 10 g = 132585.7 g = 132.59 kg.

Multiple choice
  1. 2.5 m

  2. 2.8 m

  3. 3.2 m

  4. 3 m

  5. 4 m

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let breadth = x, length = 2x. Area = 2x^2. Cost of carpet = 1 * 2x^2 = 1800 -> x^2 = 900 -> x = 30. Breadth = 30, Length = 60. Wall area = 2*(L+B)H = 2(90)*H = 180H. Wall area - 10 = (265 / 0.5) = 530. 180H = 540 -> H = 3.