Michigan Residential Builders License Practice Test

For a wall that is 40 ft long and 10 ft high, how many blocks are needed in the first course?

1. 20 blocks

2. 30 blocks

3. 40 blocks

4. 50 blocks

The correct answer is: 30 blocks

To determine the number of blocks needed for the first course of a wall that is 40 feet long and 10 feet high, it is essential to first understand the size of the blocks used. Typically, standard concrete masonry units (CMUs) or concrete blocks measure 16 inches long by 8 inches high. To convert the wall dimensions from feet to inches for compatibility with the block size: - The wall length is 40 feet, which equals 40 x 12 = 480 inches. - The wall height is 10 feet, which equals 10 x 12 = 120 inches. Next, calculate the number of blocks that can fit in the length of the wall: - Each block occupies 16 inches of length. - Thus, the number of blocks that fit in the length is 480 inches (wa wall's length) divided by 16 inches (the length of one block): 480 inches ÷ 16 inches/block = 30 blocks The height of the wall is not a factor in determining how many blocks are needed for just the first course since each course is built in the full length of the wall. Therefore, for the first course alone, you would need 30 blocks. This calculation confirms