Katalin drove 300 miles on her vacation. She drove an average of 1.9
times faster on the second 150 miles of her trip than she did on the
first 150 miles of her trip. Which expression represents the time she
spent driving? Let x = her speed on the first half of the trip.

Speed = Distance ÷ Time then Time = Distance ÷ Speed
The time taken for the first 150 miles is, 150/x
The time taken for the second 150 miles is, 150/1.9x
The time for the complete journey = 150/x + 150/1.9x = 228.95x

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