Using the formula: *Time = Distance ÷ Speed*, it would take 1 hour and 12 minutes to travel 84 miles at a constant speed of 70 mph.

When you have constant speed, the same formula pops up over and over again, and that's the formula that connects distance, speed and time.

An easy way to remember the distance, speed and time equations is to put the letters into a triangle. See image on the side.

The triangles will help you remember these 3 rules:

Distance= Speed x Time

Time= Distance/Speed

Speed= Distance/Time

You can also find the time, speed or distance in using these online calculators.

*How long would it take to drive 80 miles at 80 miles an hour?* Watch as mother-of-two is stumped by this one simple question (in a video posted by her fiancé) on DailyMail.co.uk.