Distance driven by the truck driver = 10 miles
Time taken = 1 3/4 hours
= 7/4 hours
So
10 miles is driven by the truck driver in = 7/4 hours
1 mile driven by the truck driver in = (7/4)/10 hours
= 7/40 hours
So the speed of the truck in miles per hour is 7/40 miles per hour. It can also be written as 0.175 miles per hour. I hope the procedure is clear to you. In future you can attempt such problems on your own without requiring any help from outside.
