Multiple choice

The height of a right circular cone is 24 cm and the slant height is 25 cm. Find the curved surface area. (Use pi= 22 7 )

  1. 150 cm2

  2. 550 cm2

  3. 450 cm2

  4. 750 cm2
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Radius r = sqrt(l^2 - h^2) = sqrt(25^2 - 24^2) = sqrt(625 - 576) = sqrt(49) = 7. Curved surface area = pi * r * l = (22/7) * 7 * 25 = 22 * 25 = 550.

AI explanation

First, find the base radius of the cone using the Pythagorean theorem, since the radius squared plus the height squared equals the slant height squared. This gives the radius squared as 25 squared minus 24 squared, or 625 minus 576, meaning the radius squared is 49 and the radius is 7 cm. The curved surface area of a cone is pi times the radius times the slant height, so (22/7) times 7 times 25 equals 550 cm2.

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