Katalin drove 180 miles on her vacation. She drove an average of 1.5 times faster on the second 90 miles of her trip than she did on the first 90 miles of her trip. Which expression represents the time she spent driving? Let x = her speed on the first half of the trip.

Answer 1

Time spent on the first 90 miles = 90/x
Time spent on the second 90 miles = 90/(1.5x)

Total time spent driving = 90/x + 90/(1.5x)
= 90/x + 60/x
= 150/x

Therefore, the expression representing the time Katalin spent driving is 150/x.