To find the height of the tree, we can use the concept of similar triangles. Since both George and the tree cast shadows of different lengths, we can set up a proportion based on their heights and the lengths of their shadows.
Let \( h \) be the height of the tree in feet. We have:
\[ \frac{\text{Height of George}}{\text{Shadow of George}} = \frac{\text{Height of Tree}}{\text{Shadow of Tree}} \]
Plugging in the values we have:
\[ \frac{6.25}{10} = \frac{h}{28} \]
To solve for \( h \), cross-multiply:
\[ 6.25 \cdot 28 = 10 \cdot h \]
Calculating \( 6.25 \cdot 28 \):
\[ 6.25 \cdot 28 = 175 \]
Now we have:
\[ 175 = 10h \]
Dividing both sides by 10:
\[ h = \frac{175}{10} = 17.5 \]
Thus, the height of the tree is 17.5 feet tall.