Michael drove to work at 40 mph and arrived 1
minute late.
The next day, he left at the same time and drove
the same distance to work
at 45 mph and arrived 1 minute early.
How far did Michael have to drive to work?
Solution to Problem: The answer is 12 miles.
Let T = number of hours to get to work on time.
Set up a rate-time-distance table as shown below:
| Rate | Time | Distance |
| 40 | T + 1/60 | 40 (T + 1/60) |
| 45 | T - 1/60 | 45 (T - 1/60) |
Then set 40 (T + 1/60) = 45 (T - 1/60)
40T + 2/3 = 45T - 3/4
so T = 17/60 hours or 20 minutes.
Hence, the distance = 40 (17/60 + 1/60) = 12 miles.
Correctly solved by:
| 1. Jia Ran | Rome, Italy |
| 2. Jon Pence | Winchester, VA |
| 3. Steve Muller | Clearbrook, VA |
| 4. Liz Cotter | Centreville, VA |
| 5. Bob Hearn | Winchester, VA |