The circumference of a circle is (pi) x (the diameter).
If the diameter of the wheel is 18 inches (1.5 feet), then its circumference is
(pi) x (1.5 feet) = 1.5π feet .
Every time the wheel rotates once, the car moves 1.5π feet.
1 mile = 5,280 feet
In order for the car to move 5,280 feet, the wheel has to rotate
(5,280 / 1.5π) times.
(5,280 / 1.5π) = 1,120.4508 times
Rounded to the nearest whole number: 1,120 revolutions