July 2014
Problem of the Month

Brick by Brick

The diagram below shows one face of a chimney.   No bricks were cut to form the chimney; the "half-bricks" are the ends of bricks that extend along one of the other sides.   How many bricks were needed to build the entire chimney?

Solution to the Problem:

The answer is 30 bricks; five rows of six apiece.

An aerial view of the chimney looks like this:


James Alarie noted that I did not specify a square chimney.   Here is his additional answer:

If the chimney is not square:
it might have zero space for the flue gasses (a simple slit down the
middle) and have only 4 bricks per layer for a total of 20 bricks.
it might have a flue width of 1/2 brick; 5 bricks per layer = 25 bricks total.
it might have a flue width of 1 brick (it's square); the
originally-mentioned 30 bricks total.
it might have a flue width greater than 1 brick and the total would
be 20 + 10 * width.

Correctly solved by:

1. James Alarie	Flint, Michigan
2. Chad Fore	Gate City, Virginia
3. Keith Mealy	Cincinnati, Ohio

Send any comments or questions to: David Pleacher