For the cylindrical bucket filled with sand, the volume of sand in the bucket will be given by the formula:
Volume=Area of the circular bottom x height
We know that the area of the circular bottom is given to be
and the height is 8 inches.
Therefore, Volume of Sand=

Now, for calculating the volume of water, we will employ the formula:
Volume=
x
xheight
Thus, from the given data, Volume of water is:

As can be clearly seen the volume of sand is more than the volume of water and thus there is more sand than water. The difference in their volumes is
=
.