Geometry and TrigonometryVery hardLateral surface area of a cylinder
Geometry and Trigonometry practice question
A cylindrical label wraps exactly once around the side of a can with radius 4 cm and height 10 cm, with no overlap. What is the area of the label, in square centimetres?
- A. 80πCorrect
- B. 160π
- C. 40π
- D. 112π
Answer: A. 80π
The label is a rectangle: circumference × height = 2π(4)(10) = 80π.
Why the other answers are wrong
- B. 160π
- 160π is πr²h, the volume's formula; the label is the curved side, 2πrh.
- C. 40π
- 40π uses πr × h, forgetting the 2.
- D. 112π
- 112π adds the two circular ends (2 × 16π); a label covers only 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.