If a soil area 90 feet by 60 feet is treated with a power sprayer at a dosage of one gallon per square yard of surface, what is the total amount of solution required?

If a soil area 90 feet by 60 feet is treated with a power sprayer at a dosage of one gallon per square yard of surface, what is the total amount of solution required?

• A. 600 gallons
• B. 540 gallons
• C. 720 gallons
• D. 400 gallons

Answer: (A)

The key idea is to match the dosage unit with the area unit. The sprayer rate is 1 gallon per square yard, so you must convert the area to square yards to multiply correctly. First find the area in square feet: 90 feet times 60 feet equals 5400 square feet. Since 1 square yard equals 9 square feet, convert to square yards: 5400 divided by 9 equals 600 square yards. At a rate of 1 gallon per square yard, the total volume needed is 600 gallons. So the correct total is 600 gallons. The other numbers would come from mis-converting units or misapplying the rate.

The key idea is to match the dosage unit with the area unit. The sprayer rate is 1 gallon per square yard, so you must convert the area to square yards to multiply correctly.

First find the area in square feet: 90 feet times 60 feet equals 5400 square feet. Since 1 square yard equals 9 square feet, convert to square yards: 5400 divided by 9 equals 600 square yards. At a rate of 1 gallon per square yard, the total volume needed is 600 gallons.

So the correct total is 600 gallons. The other numbers would come from mis-converting units or misapplying the rate.