To find the volume \( V \) of a cone, you can use the formula:
\[ V = \frac{1}{3} \pi r^2 h \]
where:
- \( r \) is the radius of the base of the cone,
- \( h \) is the height of the cone.
Given:
- \( r = 5 \) inches
- \( h = 15 \) inches
- \( \pi \approx 3.14 \)
Now plug in the values:
\[ V = \frac{1}{3} \times 3.14 \times (5^2) \times 15 \]
Calculating \( 5^2 \):
\[ 5^2 = 25 \]
Now substitute that back into the volume formula:
\[ V = \frac{1}{3} \times 3.14 \times 25 \times 15 \]
Now calculate \( 25 \times 15 \):
\[ 25 \times 15 = 375 \]
So the volume equation now looks like this:
\[ V = \frac{1}{3} \times 3.14 \times 375 \]
Now calculate \( \frac{1}{3} \times 375 \):
\[ \frac{375}{3} = 125 \]
So now we have:
\[ V = 3.14 \times 125 \]
Calculating that gives:
\[ V = 392.5 \]
Thus, the volume of the water the flower vase can hold is:
\[ \text{392.5 cubic inches} \]
So, the answer is 392.5 cubic inches.