Mensuration Questions

Multiple choice
  1. Curved surface of cone =20π

  2. Total surface area = 36π

  3. Volume=(80 /3)π

  4. None of these

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

Revolving a 3-4-5 triangle about the 3cm side creates a cone with height h=3, radius r=4, and slant height l=5. Curved surface area = pi*r*l = pi*4*5 = 20*pi. Total surface area = pi*r*l + pi*r^2 = 20*pi + 16*pi = 36*pi. Volume = (1/3)*pi*r^2*h = (1/3)*pi*16*3 = 16*pi. Option C claims volume is 80/3*pi, which is false.

Multiple choice
  1. 64.2

  2. 72.4

  3. 95.5

  4. 96.3

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

Surface area of a sphere is proportional to r^2. If area of B is 800% more than A, then Area(B) = 9 * Area(A), so r(B) = 3 * r(A). Volume is proportional to r^3, so Volume(B) = 27 * Volume(A). Thus, A is 26/27 of B smaller, which is approximately 96.3%.

Multiple choice
  1. 2 : 3

  2. 3 : 5

  3. 2 : 5

  4. 3 : 4

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

The curved surface area of a cylinder is given by 2 * pi * r * h, and the area of its base is pi * r^2. Setting the curved surface area equal to five times the base area gives 2 * pi * r * h = 5 * pi * r^2, which simplifies to 2h = 5r. Rearranging this equation to find the ratio of radius to height (r/h) yields 2/5, or 2 : 5.

Multiple choice
  1. Statement (1) ALONE is sufficient, but statement (2) ALONE is not sufficient.

  2. Statement (2) ALONE is sufficient, but statement (1) ALONE is not sufficient.

  3. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

  4. EACH statement ALONE is sufficient.

  5. Statements (1) and (2) TOGETHER are NOT sufficient.

Reveal answer Fill a bubble to check yourself
B Correct answer
Multiple choice
  1. Quantity A is greater.

  2. Quantity B is greater.

  3. The two quantities are equal.

  4. The relationship cannot be determined from the given data.

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

Circle area = pi * r^2 = 3.14 * 100 = 314. Square inscribed in circle has diagonal = 2r = 20. Side s = 20/sqrt(2) = 10*sqrt(2). Square area = s^2 = 200. Area not covered = 314 - 200 = 114. 114 > 30.