Question

Joe walked 4/9 mile in 4/5 of an hour what is his unit per mile

Answer 1

find common denominators and move from there

Answer 2

(4/9) mile in (4/5) hr
we want x mile in (5/5) hr
Set up a proportion.
(4/9) / (4/5) = x / (5/5)
(4/5)x = (4/9)(5/5)
(4/9)x = (4/5)(5/5)
(4/9)x = (4/5)
Multiply both sides by (9/4) to clear the fraction
x = (4/5)(9/4)
x = 9/5 hr per mile