The distance from City A to City B is 120 miles. While driving from City A to City B, Cara drives at a constant speed of 30 miles per hour. Dan leaves City A 60 minutes after Cara. What is the minimum constant speed in miles per hour that Dan must exceed in order to arrive in City B before Cara? Choose one
A) 42 B) 44 C) 46 D) 48 E) 40

Rationale: the time it takes cara to drive to city b is 120 / 30 = 4 hours . dan needs to take less than 3 hours for the trip . dan needs to exceed a constant speed of 120 / 3 = 40 miles per hour . the answer is e .
Answer: E