Geometry and TrigonometryVery hardSurface area of an open-topped cylinder
Geometry and Trigonometry practice question
An open-topped cylindrical can has a radius of 2 and a height of 3. What is the total surface area of the can, including its base but not a lid?
- A. 16πCorrect
- B. 20π
- C. 12π
- D. 28π
Answer: A. 16π
Base: π(2²) = 4π. Curved side: 2π(2)(3) = 12π. No lid. Total: 4π + 12π = 16π.
Why the other answers are wrong
- B. 20π
- 20π includes a lid (another 4π), but the can is open-topped.
- C. 12π
- 12π is the curved side alone, without the base.
- D. 28π
- 28π adds two circles of 8π (using the diameter as the radius) to the side.
More Geometry and Trigonometry questions
- Very hard
Two parallel lines are cut by a transversal. One of the eight angles measures 47°. Which of the following is N… - Very hard
In a right triangle, angles A and B are the two acute angles, so A + B = 90°. If sin A = 0.6, what is the valu… - Very hard
A regular hexagon has a side length of 4. What is its area? (A regular hexagon of side s has area (3√3/2)s².) - Very hard
A cone has a radius of 6 and a height of 10. What is its volume? (Use V = (1/3)πr²h.) - Very hard
In the xy-plane, the graph of x² + y² − 12x − 4y + 15 = 0 is a circle. The line 3x − 4y = 25 intersects this c… - Very hard
What is the perimeter of triangle ABC?
Not affiliated with the College Board. SAT is a trademark of the College Board.