a. Get 12 cubes. Put them in 3 piles.
The pile with the most cubes must have 4 cubes more than the pile with the fewest cubes.
b. Get 12 cubes. Put them in 4 piles.
The pile with the most cubes must have twice as many cubes as the pile with the fewest cubes.
c. Get 12 cubes. Put them in 3 piles.
The pile with the fewest cubes must have 6 fewer cubes than the pile with the most cubes.
Brainteaser solutions
12 cubes
A 2 cubes, 4 cubes, 6 cubes
B 2 cubes, 3 cubes, 3 cubes, 4 cubes
C 1 cube, 4 cubes, 7 cubes or 2 cubes, 2 cubes, 8 cubes