The rate is going to be the same as the distance travelled in 1 hour. The units will be different.
Formula
d = r * t
Givens
d = 558 miles
t = 3 hours
Problem A
r = d / t
r = 558/ 3 = 186 miles / hr
Problem B
Givens
r = 186 miles / hour
t = 1 hour
d = ?
Solution
d = 186 mi/hr * 1 hr
d = 186 miles
<u>Note</u>
This looks really trivial, but it's not. You have to learn to see the difference between a number and its units. It's not very often that the numbers will be the same, but if the units differ, then it is an entirely different question.