How to Find the Volume of a Cylinder

Step-by-step solution

1. Write the volume formula.

   $$V = \pi r^2 h$$

   Why: A cylinder is a circle of area pi r squared, stacked to height h.

2. Substitute the values.

   $$V = \pi \times 3^2 \times 5$$

   Why: The radius is squared and multiplied by the height.

3. Multiply and estimate.

   $$V = 45\pi \approx 141.4$$

   Why: The exact answer keeps pi; 45 x 3.14 gives the decimal.

Practice problems

Use the same method. Work each problem on paper, then open the answer to check.

1. 1

   $r = 2,\quad h = 7$

   Show answer

   $V = 28\pi$

2. 2

   $r = 4,\quad h = 3$

   Show answer

   $V = 48\pi$

3. 3

   $r = 5,\quad h = 2$

   Show answer

   $V = 50\pi$

4. 4

   $r = 1,\quad h = 10$

   Show answer

   $V = 10\pi$

5. 5

   $r = 3,\quad h = 8$

   Show answer

   $V = 72\pi$