Answer: There are 14 boxes that can be fit on a shelf.
Explanation:
Since we have given that
Length of cracker box = 12 in.
Width of cracker box = 10 in.
Height of cracker box = 2 in.
So, Area of base of cracker box is given by

And the dimensions of shelf is
Length = 20 inch
Width = 14 inch
So, Area will be

So, Number of boxes can be fit on the shelf is given by

Hence, there are 14 boxes that can be fit on a shelf.