To find the new width in boxes after changing the scale, you start with the original width of 3 boxes. Since the new scale is 1 box = 2 inches instead of 4 inches, the drawing has to be larger in boxes to maintain the same size in inches.
Since the new scale is half (2 inches compared to 4 inches), you double the number of boxes. So, 3 boxes x 2 = 6 boxes.
The new width in the drawing will be 6 boxes.