The odometer of the family car shows 15,951 miles.
The driver noticed that this number is palindromic:
It reads the same backward as forward.
"Curious," the driver said to himself, "It will be a long time
before that happens again."
But two hours later, the odometer showed a new palindromic number.
How fast was the car traveling in those two hours?
You may assume that the driver does not go over 100 mph!
Solution to the Problem:
The driver was going 55 mph.The first digit of 15951 could not change in two hours.
Therefore, 1 is the first and last digit of the new number.
The second and fourth digits changed to 6.
The middle digit could be 0, 1, 2, 3, ... 9.
So, the miles driven would be 110, 210, 310, ... respectively.
In two hours, the car would have gone at a speed of 55 mph, 105 mph, 155 mph, ... respectively.
Correctly solved by:
| 1. James Alarie | Flint, Michigan |
| 2. Alp Aribal | Istanbul, Turkey |
| 3. Dakota Rees |
Mountain View High School, Mountain View, Wyoming |
| 4. Chad Fore | Gate City, Virginia |
| 5. Brandon Cheng |
Farmington High School Farmington, Connecticut |
| 6. Rachel Hofer |
Mountain View High School, Mountain View, Wyoming |
| 7. Matt Zadra |
Mountain View High School, Mountain View, Wyoming |
| 8. David & Judy Dixon | Bennettsville, South Carolina |
| 9. Matt Hale |
Mountain View High School, Mountain View, Wyoming |
| 10. Cassie Warren |
Mountain View High School, Mountain View, Wyoming |
| 11. Alexis Condos |
Mountain View High School, Mountain View, Wyoming |
| 12. Riley Dolezal |
Mountain View High School, Mountain View, Wyoming |
| 13. Aubrey Newton |
Mountain View High School, Mountain View, Wyoming |
| 14. Karsten Hauf |
Mountain View High School, Mountain View, Wyoming |
| 15. John C. Funk | Ventura, California |
| 16. Alex Snyder |
Mountain View High School, Mountain View, Wyoming |
| 17. Alyssa Sibelrud |
Mountain View High School, Mountain View, Wyoming |
| 18. Marissa Vitt |
Mountain View High School, Mountain View, Wyoming |
| 19. Kalvin Hereford |
Mountain View High School, Mountain View, Wyoming |
| 20. Kaylor Dolezal |
Mountain View High School, Mountain View, Wyoming |
| 21. Josey Pitts |
Mountain View High School, Mountain View, Wyoming |
| 22. Isaac Kampman | ---------- |
| 23. Michael Brown |
Mountain View High School, Mountain View, Wyoming |