Find the surface area and volume of a sphere that has a diameter of

50
50 inches. Use 3.14 for π. Click Here for Help Video

The sphere's surface area is
square inches.

The sphere's volume is
cubic inches.

1 answer

To find the surface area and volume of a sphere, we can use the following formulas:

  1. Surface Area (A) of a sphere:
    \[ A = 4\pi r^2 \]
  2. Volume (V) of a sphere:
    \[ V = \frac{4}{3}\pi r^3 \]

Given that the diameter of the sphere is 50 inches, we can find the radius by dividing the diameter by 2:
\[ r = \frac{50}{2} = 25 \text{ inches} \]

Surface Area Calculation

Using the surface area formula:
\[ A = 4\pi r^2 \] Substituting \(r = 25\) inches and \(\pi = 3.14\): \[ A = 4 \times 3.14 \times (25)^2 \] Calculating \((25)^2\): \[ 25^2 = 625 \] Now substituting back: \[ A = 4 \times 3.14 \times 625 \] Calculating \(4 \times 3.14\): \[ 4 \times 3.14 = 12.56 \] Now, \[ A = 12.56 \times 625 \] Finally, calculating \(12.56 \times 625\): \[ A = 7850 \text{ square inches} \]

Volume Calculation

Using the volume formula:
\[ V = \frac{4}{3}\pi r^3 \] Substituting \(r = 25\) inches and \(\pi = 3.14\): \[ V = \frac{4}{3} \times 3.14 \times (25)^3 \] Calculating \((25)^3\): \[ 25^3 = 15625 \] Now substituting back: \[ V = \frac{4}{3} \times 3.14 \times 15625 \] Calculating \(\frac{4}{3} \times 3.14\): \[ \frac{4 \times 3.14}{3} = \frac{12.56}{3} \approx 4.1867 \] Now, \[ V = 4.1867 \times 15625 \] Calculating \(4.1867 \times 15625\): \[ V \approx 65261.25 \text{ cubic inches} \]

Final Results

  • The sphere's surface area is approximately 7850 square inches.
  • The sphere's volume is approximately 65261.25 cubic inches.