Tommy bought a new drum, which is a cylindrical shape. Its diameter is 14 inches and height is 15 inches. What is the approximate surface area of Tommy's drum?

(1 point)
Responses

967.61 square inches
967.61 square inches

1891.24 square inches
1891.24 square inches

813.67 square inches
813.67 square inches

2309.07 square inches
2309.07 square inches

1 answer

To calculate the surface area of a cylindrical drum, we use the formula:

\[ \text{Surface Area} = 2\pi r^2 + 2\pi rh \]

where:

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

Given:

  • Diameter = 14 inches, therefore the radius \( r = \frac{14}{2} = 7 \) inches,
  • Height \( h = 15 \) inches.

Now we can substitute these values into the formula:

  1. Calculate the area of the two circular bases: \[ 2\pi r^2 = 2\pi (7^2) = 2\pi (49) = 98\pi \approx 307.76 \text{ square inches} \]

  2. Calculate the lateral surface area: \[ 2\pi rh = 2\pi (7)(15) = 210\pi \approx 659.73 \text{ square inches} \]

  3. Now add the areas together: \[ \text{Total Surface Area} = 98\pi + 210\pi = 308\pi \approx 967.65 \text{ square inches} \]

Rounding this to the nearest hundredth, we find:

\[ \text{Total Surface Area} \approx 967.61 \text{ square inches} \]

Thus, the approximate surface area of Tommy's drum is:

967.61 square inches.