How much larger is the calculation of the volume of a sphere's whose radius is

39 inches if π is used instead of 3.14?

Round your answer to the nearest tenth.

1 answer

To find out how much larger the calculation of the volume of a sphere is when using \(\pi\) as opposed to using \(3.14\), we'll first need to calculate the volume of a sphere using both values for \(\pi\).

The formula for the volume \(V\) of a sphere is given by:

\[ V = \frac{4}{3} \pi r^3 \]

where \(r\) is the radius of the sphere.

1. Calculating volume using \(\pi\):

  • Given that the radius \(r = 39\) inches, the volume using \(\pi\) is:

\[ V_\pi = \frac{4}{3} \pi (39)^3 \]

Calculating \(39^3\):

\[ 39^3 = 59319 \]

Then substituting back into the formula:

\[ V_\pi = \frac{4}{3} \pi (59319) = \frac{4 \times 59319}{3} \pi = \frac{237276}{3} \pi = 79192 \pi \]

Using \(\pi \approx 3.14159\):

\[ V_\pi \approx 79192 \times 3.14159 \approx 248,159.6 \text{ cubic inches} \]

2. Calculating volume using \(3.14\):

  • Now using \(3.14\) instead of \(\pi\):

\[ V_{3.14} = \frac{4}{3} (3.14) (39)^3 \] \[ V_{3.14} = \frac{4}{3} (3.14) (59319) = \frac{4 \times 3.14 \times 59319}{3} \]

Calculating \(4 \times 3.14 = 12.56\):

Now, evaluate \(12.56 \times 59319\):

\[ 12.56 \times 59319 \approx 745,736.44 \]

Now divide by 3:

\[ V_{3.14} = \frac{745736.44}{3} \approx 248578.81 \text{ cubic inches} \]

3. Finding the difference: Now, we find the difference in the volumes:

\[ \text{Difference} = V_\pi - V_{3.14} \approx 248159.6 - 248578.81 \approx -419.21 \]

This means the volume with \(3.14\) is actually larger than with \(\pi\). To find how much larger:

\[ \text{Difference} = 248578.81 - 248159.6 \approx 419.21 \]

4. Rounding to the nearest tenth:

The final calculation is:

\[ \text{Difference} \approx 419.2 \text{ cubic inches} \]

So, the calculation of the volume of a sphere whose radius is 39 inches is approximately 419.2 cubic inches larger when using \(3.14\) instead of \(\pi\).