Make a Fermi estimate of the number of bricks that would fit into a refrigerator.
Use reasonable values for a standard-sized brick and a typical refrigerator.
figure a brick is 8x4x2 inches
3x6x3 = 54 bricks is 2 cubic feet
a fridge is about 6 foot high, 3 foot wide, 2 foot deep or 36 cubic feet.
36/2 = 12 x 54 = 648 bricks