The skill of dividing square feet is a useful one for various reasons. One common application for landscapers is to figure out how much fertilizer or pest control to apply to cover a particular size lawn. Gardeners can size their beds and purchase the number of seeds and plants they need with more accuracy if they know how to divide the square footage of each area. Just as any other numbers are divided, square feet may be divided, too.
Determine the Total Square Feet
Write down the total square footage of the area that you want to divide. Using a lawn that you want to fertilize as an example, say that the lawn has 100 feet of road frontage and is about 25 feet deep. The formula for the area is length times width, so 100 times 25 equals 2,500 square feet.
Say that a side patch of lawn that you might also want to fertilize is 50 feet long by 10 feet deep. Fifty times 10 equals 500 square feet. Add the 2,500 square feet of the front lawn to the 500 square feet of the side lawn to get a total of 3,000 square feet.
Calculate the number of bags of fertilizer you need to buy. Since fertilizer typically comes in bags that cover about 1,000 square feet and you need to cover 3,000 square feet, divide 3,000 by 1,000. The answer is three.
Subtract and Divide to Create Portions
Divide the fertilizer to designate amounts for each lawn. There are two ways to do this. An easy way is to set aside two of the bags and designate them to cover 2,000 square feet of the front lawn, since each bag will cover 1,000 square feet.
Subtract the 2,000 square feet from 3,000 square foot area that you need. The answer is 1,000.
Divide this bag into two equal portions, since you need 500 square feet each for the side lawn and the remaining amount of front lawn.
Calculate Percentages Algebraically to Create Portions
Calculate algebraically (without first subtracting the 2,000) by figuring out the portions needed for each lawn by dividing the square footage. Figure the percentage to find the answer.
Write the equation to find what percentage 2,500 is of 3,000, which algebraically is: 2,500 = X/100 * 3,000, since percentage is how much per 100. Solve the equation by isolating X. Divide each side by 3,000. Now the equation reads: 2,500/3,000=X/100 (3,000/3,000). Reduce: .833 = X/100. Multiply each side by 100 to get .833_100=X/100_100. Solve: X=83.3 percent.
Divide your bags so that you will use 83.3 percent of the total amount of fertilizer for the front lawn. 83.3 percent of three bags equals .833 times three. Find the solution to be two and a half bags (2.5).
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