I don't know how to calculate how long the 'tip' took. I don't even see where anyone in the story got a tip, unless you count the information I'm giving you here a tip.
If you need to know how long the trip took, think about what "mph" means. Miles per hour, specifically for this problem 60 miles per hour. That means every hour, the car goes 60 miles. How many segments of 60 miles are in 300 miles? The trip will take one hour for each of those 60 mile segments. Another way to put it is: How many times does 60 go into 300?
John
My calculator said it, I believe it, that settles it
