One particularly large ant hill found in 1997 measured 40 inches wide at the base and 18 inches high. what was the slope of the ant hill

The slope of the ant hill is 18/20 or 0.9.

For the slope, we need to put the vertical change over the horizontal change. In this case, the vertical change of the ant hill is 18.

Now for the horizontal change, the entire base is 40. However, we only need half of that because we need the distance from the outside to the middle where the height is. Half of 40 is 20.

Therefore, the slope is up 18 over 20. Or 18/20 = 0.9.