## Elementary Technical Mathematics

Fist find the surface area of the walls. Since the block size is given in inches, convert the wall measurements to inches. The height of the walls are 8 ft. $8 ft \times \frac{12 in}{1 ft} = 96 in$ The width of the back and front walls is 17 ft 4 in. $17 ft \times \frac{12 in}{1 ft} = 204 in$ $17 ft 4 in = 204 in + 4 in = 208 in$ The width of the side walls is 12 ft 8 in. $12 ft \times \frac{12 in}{1 ft} = 144 in$ $12 ft 8 in = 144 in + 8 in = 152 in$ Calculate and sum the areas of each wall. $(208 \times 96) + (208 \times 96) + (152 \times 96) + (152 \times 96) = 19968 + 19968 + 14592 + 14592 = 69120 sq\ in$ Find the area covered by each block by multiplying the length and height. The thickness of the block is not a factor in determining the area covered. $16\times 8 = 128sq\ in$ Divide the total area to be covered by the block size to find the total number of blocks needed. $69120\div 128 = 540\ blocks$