As a trains engineer, erin guided the train on a 64 mile run which took 1.7 hours. she then stopped on a side rail to let a second train pass. she then continued another 80 miles, which took 1.9 hours what was the trains average speed for the entire run? there are no answer choices!

To find the rate (or speed) of an object you use the equation

Rate = Distance x Time or 

d = rt          So, just fill in the equation with the first set of numbers.
64 = r(1.7)    Then divide.
r ≈ 37.65

Then, find the second speed.
d = rt
80 = r(1.9)    And divide.
r ≈ 42. 11

Since you need to find the average speed just find the average of the two speeds. So

(42.11 + 37.65) / 2

79.76 / 2

39.88

So the average speed of the train was about 39.9 miles per hour.