Question

A 1/2-mile long train enters a 2-mile long tunnel traveling at a speed of 10 mi/h. How many minutes pass from the time the front of the first train car enters the tunnel until the rear of the last train car exits the tunnel?

Answer 1

• 15 min

Explanation:

The distance required is the length of the tunnel added to the length of the train

• d = 1/2 + 2 = 5/2 miles
• s = 10 mile/hour = 10/60 mile/min= 1/6 mile/min

Time is:

• t = d/s
• t = 5/2 : 1/6 = 5/2*6= 15 min