Atrain travels 54 kilometers in one hours, and then 85 kilometers in 3 hours. what is its average speed?

Hey there! :D

So, we need to find how many miles would be traveled per hour in the 85 miles in 3 hours time frame. 

85/3= 28 1/3

So, we could represent this like a sequence of numbers and find the mean. (which is just the average) 



Add all the numbers together. 



Since this was in a span of four hours. 1+3=4, we can divide this by 4 to find the average. 



The average was 34.75 miles per hour. 

I hope this helps!
~kaikers