0910.1: Solution


 

Congratulations to Brian Watt '13 for winning the first logic puzzle contest of the year.

 

Correct answers were also submitted by:

 

Kiernan Acquisto '13, Jeremy Adelman '13, Andrew Beyler '10, Beaumont Brians '13, Robert Bryan '11, Linnaea Chapman '10, Ellie Fausold '13, Alex Gross '11, Jess Gutfleish '13, Alex Host, '13, Mikayla Irle '12, Sarah Krieger '11, Rachel Slivken '13, Drew Upright '13, Evan van Tassell '13, and Tom Williams '11

 

and

 

Lydia Hamessley (Music) and Amy Lytle (Physics)

 

Here is a method for determining the solution, with a chart for the solution below:

 

1 conflicts with 3 (since the person who lives in Root can not be the person who lives in Wertimer).  1 also conflicts with 7 (since the Buffers are all male).  So, 1 must be false, and the other statements are veridical.

Next, we can determine the physics major.  From 2, it is neither Emil nor Bhavin.  From 3 and 4, it can not be Frank.  The physics major had his/her first class fifth (from 4).  So, the physics major can not be Charlotte, who had her first class second, just after the person who lives in Wertimer (from 6 and 3).  And, it can not be Andrea, who had her first class fourth, two after Charlotte (from 6).  So, the physics major must be Deborah, who arrived on campus second and had her first class fifth.

Frank arrived last (from 3), Charlotte arrived fifth, and and Emil arrived fourth (from 6).  The first person to arrive thus must be Andrea or Bhavin.  But, Andrea has her first class fourth, and the first person to arrive has his/her first class last.  So, the first person to arrive must be Bhavin, who has his first class last, lives in South, and majors in economics.  Andrea must thus have arrived third.

We have assigned positions in the ordering of first classes to everyone except Emil and Frank, and first and third positions remain.  Frank can not be first (from 3), so Emil must have had his first class first, and Frank had his third.  Emil lives in Wertimer (from 3).  Frank majors in psychology (from 4).

Either Andrea, Charlotte, or Emil must be the philosophy major.  It must be Andrea (from 7), since Charlotte arrived fifth and Emil arrived fourth.  Since Emil, who lives in Wertimer, can’t be the math major (from 7), he must be the art major, and Charlotte must be the math major.

Frank lives in Root (from 6).  Deborah (the physics major) can’t live in Minor or Dunham (from 2), so must live in Bundy.  By 8, Andrea (philosophy) lives in Minor.  And, Charlotte lives in Dunham.

 

Person

Dorm

Major

Arrival

First Class

Andrea

Minor

Philosophy

3

4

Bhavin

South

Economics

1

6

Charlotte

Dunham

Mathematics

5

2

Deborah

Bundy

Physics

2

5

Emil

Wertimer

Art

4

1

Frank

Root

Psychology

6

3