Answer to the Problem of the Week
for the week of November 7, 2005

What Day of the Week is it?
from Car Talk

Ashley, Britney, Charles, David, Erika, Frank, and Gusti are having an argument about which day of the week it is.   They speak as follows:

Ashley: The day after tomorrow is Wednesday.
Britney: No, it is Wednesday today.
Charles: You are both wrong; it is Wednesday tomorrow.
David: Nonsense. Today is neither Monday, Tuesday, nor Wednesday.
Ericka: I'm quite sure yesterday was Thursday.
Frank: No, tomorrow is Thursday.
Gusti: All I know is that yesterday was not Saturday.

If only one of the remarks is true, what day of the week is it?



 

Solution to the Problem:

Today is Sunday.

We rewrite the statements in the following form:

Today is Monday.
Today is Wednesday.
Today is Tuesday.
Today is either Thursday, Friday, Saturday or Sunday.
Today is Friday.
Today is Wednesday.
Today is either Saturday, Monday, Tuesday, Wednesday, Thursday or Friday.

The only day that is not mentioned twice is Sunday, so today is Sunday!




Correctly solved by:

1. Jim Arrsion Norristown, Pennsylvania
2. Sagar Patel Columbus, Georgia
3. Walt Arrison Philadelphia, Pennsylvania
4. Misty Carlisle Cornell University
Ithaca, New York
5. Mike Singer Winchester, Virginia
6. David & Judy Dixon Bennettsville, South Carolina
7. Erin Fennacy Fresno, California
8. Jeffrey Gaither University of Virginia
Charlottesville, Virginia
9. Mary Bailey Wickham Columbus, Georgia
10. Charles Washington Winchester, Virginia
11. Zaza Carlzon Tullangsskolan, Örebro, Sweden
12. Malin Fredriksson Tullängsskolan, Örebro, Sweden
13. Patrick McDuffee Harrisonburg, Virginia
14. Danny Gordon Columbus, Georgia
15. Anil Nataraj Columbus, Georgia
16. Rachel Pridgen Columbus, Georgia
17. Jerome Pierce Columbus, Georgia
18. Patrick Chu Harrisonburg, Virginia
19. Nicole Wells ----------
20. Julianne Harris Winchester, Virginia
21. Evelyne Stalzer Montville, New Jersey
22. Adam Haglund Tullängsskolan, Örebro, Sweden
23. Bobby Arthur Winchester, Virginia
24. Carleton 'Buck' Jones Midwestern University - Glendale
Glendale, Arizona
25. Nicholas Caligaris Columbus, Georgia
26. Andrew Montoya Winchester, Virginia
27. Krystle Harrisonburg, Virginia
28. Mattias Tyresgård Tullängsskolan, Örebro, Sweden
29. Rickard Jansson Tullängsskolan, Örebro, Sweden
30. Chelsea Cockburn Harrisonburg, Virginia
31. Olivia Quach Harrisonburg, Virginia
32. Joakim Olsson Tullängsskolan, Örebro, Sweden
33. Richard Johnson La Jolla, California
34. Ashley Hudson Harrisonburg, Virginia
35. Magdalena Axelsson Tullängsskolan, Örebro, Sweden
36. Annie Craig Harrisonburg, Virginia
37. Tim Beierle Harrisonburg, Virginia
38. Kelsey Wong Harrisonburg, Virginia
39. Heather Carroll Winchester, Virginia
40. Kelley Kolar Winchester, Virginia
41. Elizabeth Carlson Winchester, Virginia