The midpoint of two coordinates is the average of their $x$-coordinates and the average of their $y$-coordinates.
So, the $x$-coordinate of the midpoint is $(0 + (-4))/2 = -2$, and the $y$-coordinate of the midpoint is $(7 + (-1))/2 = 3$.
Therefore, Mark and Sandy will meet at the coordinate $\boxed{(-2,3)}$.
The answer is: (-2,3)
Below is a math problem. Provide a detailed, step-by-step solution.

### Problem:
Mark and Sandy are walking to the convenience store at the midpoint of their coordinates. Mark is standing at $(0,7)$, and Sandy is standing at $(-4,-1)$. At what coordinate will they meet?

### Answer:
