A football coach makes his players run two laps around the football field to warm up before practice. If the field is 120 yards long and 160 feet wide, how many miles do the players run to warm up? (Hint: There are 3 feet in a yard and 5,280 feet in a mile.)
Explanation
Before you do any major calculations, try to get all of the numbers in the same unit. Here we choose to convert 120 yards to feet:
\(\frac{120 \mathrm{} \mathrm{yards}}{x}=\frac{1 \mathrm{yard}}{3 \mathrm{feet}}\)
\(120 \times 3=1 x\)
\(360=x\)
Now that you know the football field is 360 feet long and 160 feet wide, you can find how far one lap around the field is by adding all four sides (a football field is a rectangle):\(360+160+360+160=1,040 \text { feet }\)
The coach makes his players run two laps, so the players run \(1,040 \times 2=2,080 \text { feet }\). Since all of the answer choices are in miles, we need to convert 2,080 feet to miles:
\(\frac{2,080 \mathrm{feet}}{x}=\frac{5,280 \mathrm{feet}}{1 \mathrm{mile}}\)
\(2,080 \times 1=5,280 x\)
\(x=0.4 \text { miles }\)