Question

Aleksandr has a roll of paper that is in the shape of a right circular cylinder. It has a height of 28 cm and a diameter of 15.5 cm. Help Aleksandr solve for the surface area. Use 3.14 for π
.(1 point)
Responses

4,234.29 cm2
4,234.29 cm squared

1,362.76 cm2
1,362.76 cm squared

1,739.95 cm2
1,739.95 cm squared

1,508.77 cm2

1 answer

To find the surface area of a right circular cylinder, we can use the formula:

\[ \text{Surface Area} = 2\pi r(h + r) \]

where:

  • \( r \) is the radius of the base,
  • \( h \) is the height of the cylinder.

Given:

  • Diameter = 15.5 cm, so the radius \( r = \frac{15.5}{2} = 7.75 \) cm
  • Height \( h = 28 \) cm
  • Using \( \pi \approx 3.14 \)

Now, we can calculate the surface area:

  1. Calculate \( h + r \): \[ h + r = 28 + 7.75 = 35.75 , \text{cm} \]

  2. Substitute \( r \), \( h \), and \( \pi \) into the surface area formula: \[ \text{Surface Area} = 2 \times 3.14 \times 7.75 \times 35.75 \]

  3. Calculate \( 2 \times 3.14 = 6.28 \)

  4. Now multiply by \( r \): \[ 6.28 \times 7.75 = 48.7575 \]

  5. Then multiply by \( h + r \): \[ 48.7575 \times 35.75 \approx 1748.03125 \]

Thus, the surface area of the cylinder is approximately \( 1748.03 , \text{cm}^2 \).

Looking at the provided options, it appears that the closest match is:

1,739.95 cm²

So the final answer is 1,739.95 cm².