The Bricklayer's Formula

Dane Baker
November 29, 2013

In this project, we had to measure several parts of a brick wall in feet. We were told to use the formula N=7LH where l stands for length and h stands for height to figure out how many bricks were in that section in the wall. If the formula did not work we had to make our own formula and test it out.

I started out with measuring three parts of the wall. One part was 3 ft by 1 ft, another was 4 ft by 3 ft, and the last was 5 ft by 3 ft. I then counted how many bricks were inside those areas. In the 3 ft by 1 ft there were 16 bricks. In the 4 ft by 3 ft there were 54 bricks. In the 5 ft by 3 ft there were 72 bricks.

I started to test out the formula. I did 7 x 3 x 1=21. That wasn't how many bricks I counted so I tried a different one. I did 7 x 4 x 3=84. Eighty-four was way above my count so I tried the last one. I did 7 x 5 x 3=105. That wasn't the same number I counted. I clearly needed to make a new formula.

I made the new formula by guessing and checking. The bricks in the wall were very uneven so I had to round to make the formula approximately the right answer. I tried 5 first. I did 5 x 3 x 1=15. That was really close so I tried a little higher. I did 5.3 x 3 x 1=16! That was how many I counted so I tried it on the other ones. I did 5.3 x 4 x 3=63.6. That was too high so I tried lower. I did 4.5 x 4 x 3=54! That was what I counted but that was lower than 5.3 so I did the average of the two which is 4.9. I tried 4.9 x 5 x 3=73.5. That was almost right and so I kept it at 4.9 because the wall was uneven. My new formula ended up being 4.9 x L x H .