Isabella is covering a square tabletop with square mossaic tiles. the tabletop is 2ft. long and 2ft. wide. each tile is 1/4 in. long and 1/4in. wide. what is the minimum number of tiles needed to cover the tabletop?

Convert the feet to inches first.  2 ft = 24 inches.  We must divide this total length by the length of each tile to determine how many tiles will fit across the tabletop:

24 ÷ (1/4) = (24/1) ÷ (1/4) = (24/1) × (4/1) = 96/1 = 96

96 tiles will fit across the tabletop.
Since the tabletop is as long as it is wide, that means we will have 96 rows of 96 tiles:
96(96) = 9,216 tiles to cover the tabletop.