Answer:
About 2.17 feet.
Step-by-step explanation:
Let <em>d</em> represent the diameter of the tire.
Then the circumference of the tire will be:
![C=d\pi](https://tex.z-dn.net/?f=C%3Dd%5Cpi)
So, the tire will travel dπ miles after one rotation.
After 775 rotations, the total miles traveled should be 5280 feet. Thus:
![775(d\pi)=5280](https://tex.z-dn.net/?f=775%28d%5Cpi%29%3D5280)
Solve for <em>d:</em>
<em />
<em />
Approximate:
![d=2.1686...\approx2.17](https://tex.z-dn.net/?f=d%3D2.1686...%5Capprox2.17)
The circumference of the tire should be about 2.17 feet.