Multiple choice

What is the surface area of a cylinder that has a top and bottom if the height is $8.5$ units and the diameter is $3$ units?

  1. $18\pi$ square units
  2. $30\pi$ square units
  3. $32\pi$ square units
  4. $36\pi$ square units
  5. $54\pi$ square units
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Surface area of a cylinder = 2 * pi * r * h + 2 * pi * r^2. Diameter = 3, so radius r = 1.5. Height h = 8.5. Area = 2 * pi * 1.5 * 8.5 + 2 * pi * 1.5^2 = 25.5 * pi + 4.5 * pi = 30 * pi.

AI explanation

The total surface area of a closed cylinder is given by the formula A = 2 * pi * r * h + 2 * pi * r^2. Given a diameter of 3 units, the radius is 1.5 units, and the height is 8.5 units. Substituting these values gives 2 * pi * 1.5 * 8.5 + 2 * pi * 1.5^2 = 25.5 * pi + 4.5 * pi = 30 * pi square units. The surface area is 30 * pi square units.

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