Answer:
50 minutes
Step-by-step explanation:
Steve has a head start of ...
(2/3 h)(25 mi/h) = 50/3 mi
Frank's closing speed is 45 -25 = 20 mi/h, so can make up that distance in ...
(50/3 mi)/(20 mi/h) = 50/60 h = 50 minutes
It takes Frank 50 minutes to overtake Steve.