Answer:
168.75 minutes
Explanation:
Francine's speed (the unit rate) is (16 miles) / (45 minutes), or 16/45 miles/min.
Recalling that distance = speed times time, we recognize that
time = distance / speed
which here is
(60 miles) / (16/45) miles/min = 168.75 minutes, or 168 min 45 sec