A toy designer is creating a basketball plushy. The designer has fabric that measures 171.9 sq. in. What is the maximum radius of the basketball that the designer can create? Use 3.14 for π.

13.7 in
6.9 in
3.7 in
3.4 in

1 answer

To find the maximum radius of the basketball plushy that can be created from 171.9 square inches of fabric, we start with the formula for the surface area of a sphere, which is given by:

\[ A = 4\pi r^2 \]

Where:

  • \( A \) is the surface area,
  • \( r \) is the radius,
  • \( \pi \) is approximately 3.14.

We want to solve for \( r \) by setting \( A = 171.9 \) square inches:

\[ 171.9 = 4 \cdot 3.14 \cdot r^2 \]

First, we calculate \( 4 \cdot 3.14 \):

\[ 4 \cdot 3.14 = 12.56 \]

Now we can substitute this back into the equation:

\[ 171.9 = 12.56 \cdot r^2 \]

Next, we divide both sides by 12.56 to isolate \( r^2 \):

\[ r^2 = \frac{171.9}{12.56} \]

Calculating the right side:

\[ r^2 \approx \frac{171.9}{12.56} \approx 13.68 \]

Now we take the square root of both sides to find \( r \):

\[ r \approx \sqrt{13.68} \approx 3.7 \]

Therefore, the maximum radius of the basketball plushy that can be created is approximately \( 3.7 \) inches.

Thus, the correct answer is:

3.7 in