Let the distance between the persons be \( D \).
From the geometry of the situation, we know the angles of elevation and the height of the tower.
Using the tangent of the angles, we can write two equations:
\[
\tan 30^\circ = \frac{45}{D_1}, \quad \tan 60^\circ = \frac{45}{D_2}
\]
Now, calculate the distances \( D_1 \) and \( D_2 \), and then find the total distance \( D = D_1 + D_2 \).