Solution:  20

Since, the ratio of the area of the larger pen to the smaller pen is 6:1

Also, the area of the larger pen is 48 square yards

Therefore, the area of larger pen can be calculated by

6/1 = 48/area of smaller pen

Therefore, area of smaller pen = 8 square yards.

Now from the questions we have, each pen can hold 1 pig for 2 square yards of its area.

Therefore, the number of pigs that the large pen and smaller pen can hold are 48/2, 8/2 respectively.

The difference (24 -4 = 20) gives us the number of pigs the larger pen can hold more than the smaller pen.