December 2–December 8, 2008

Problem

What is the smallest perfect square that ends in the four digits 9009 (in base 10, as usual)? Can you find the solution without a brute-force computer search?

Solution

here

List of solvers

Trey Sakazaki (elementary); Steve Wilmarth, Angelo Godbey, Matt Inouye, (undergrad); Jacob Lewis, Dustin Moody (graduate); Gary Raymond (staff); Lloyd Sakazaki, Dean Anderson, Mike Goodman (outside)

Matt Inouye wins the prize!