Difference between revisions of "1997 AIME Problems/Problem 8"

 
m
Line 1: Line 1:
 
== Problem ==
 
== Problem ==
 +
How many different <math>4\times 4</math> arrays whose entries are all 1's and -1's have the property that the sum of the entries in each row is 0 and the sum of the entires in each column is 0?
  
 
== Solution ==
 
== Solution ==
 +
{{solution}}
  
 
== See also ==
 
== See also ==
* [[1997 AIME Problems]]
+
{{AIME box|year=1997|num-b=7|num-a=9}}

Revision as of 15:33, 20 November 2007

Problem

How many different $4\times 4$ arrays whose entries are all 1's and -1's have the property that the sum of the entries in each row is 0 and the sum of the entires in each column is 0?

Solution

This problem needs a solution. If you have a solution for it, please help us out by adding it.

See also

1997 AIME (ProblemsAnswer KeyResources)
Preceded by
Problem 7
Followed by
Problem 9
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
All AIME Problems and Solutions
Invalid username
Login to AoPS