Thinking that “first half of the route” refers to time is a reading comprehension problem. When I first encountered the problem, I noticed the possible ambiguity (huh, did they refer to time or to distance?), then resolved it (in case of time they’d have referred to “first half of day” instead), then wrote an equation in my mind and solved it.
Thinking that “first half of the route” refers to time is a reading comprehension problem. When I first encountered the problem, I noticed the possible ambiguity (huh, did they refer to time or to distance?), then resolved it (in case of time they’d have referred to “first half of day” instead), then wrote an equation in my mind and solved it.