Question

As the train’s engineer, Erin guided the train on a 64 mi run, which took 1.7 h. She then stopped on a side rail to let a second train pass. She then continued another 80 mi, which took 1.9 h.

What was the train’s average speed for the entire run?

Answer 1

`(144 miles)/(3.6 hours)= 40 (m)/(h)`Let's calculate how many miles the train has passed in total:
64+80=144 miles

let's also calculate the complete time: (we can ignore the waiting time here, since they also didn't move during this time:

1.7h+1.9h=3.6 hours.

And now we only need to divide the distance per time:

So the correct answer is 40 miles per hour!