The tires are similar in shape. This means that if they undergo the same number of revolutions, the ratio of the distances covered would be equal to the ratio of the radius of each tire.
From the information given,
radius of tire 1 = 9
distance covered by tire 1 = 8482
let radius of tire 2 = r
distance covered by tire 2 = 5654
Thus,
8482/5654 = 9/r
By crossmultiplying, we have
r * 8482 = 5654 * 9
8482r = 50886
r = 50886/8482
r = 5.9993
By rounding to the nearest whole number,
radius of second tire = 6 inches