To put the question in slightly different words: "What is Tyler's speed ?"
I said it that way because everybody knows the simple formula for speed:
Speed = (distance covered) / (time to cover the distance)
We know both of those numbers, so all we need to do is to pluggum in:
Speed = (1/4 mi) / (1/12 hr)
(1mi/4) ÷ (1hr/12) = (1mi/4) · (12/1hr) = (12mi / 4hr) = 3 mi/hr