Presented by Cold Stone Creamery(R)
The Department of Mathematics Challenge of
the Week
A solution and a new problem is posted every Monday during fall and spring semesters at www.cs.colostate.edu/~rmm
Email your solutions to solution@math.colostate.edu
One winner each
week is eligible for a free ice cream and topping, courtesy of Cold Stone
Creamery.
Challenge 4, Fall '04
Contributed by Gary Rubinstein, Stuyvesant High School, New York
Let us call a positive integer a jackpot if its base-10 representation
consists of a sequence of one or more 7's followed by a sequence of zero
or more 0's.
For instance, 77777000 is a jackpot, as is 777.
Problem: Show that every positive integer has a multiple that is a
jackpot.
Previous Challenges, Fall '04
Challenge 1
Challenge 2
Challenge 3
If you would like to receive a weekly email reminder about the Challenge Problem, send an email to
solution@math.colostate.edu
The Department of Mathematics Challenge Problem is
sponsored by the Cold Stone Creamery, which is providing all the
prizes.
If more than one correct solution is submitted, the cleverest
or simplest solution will be selected as the winner. Submissions from
faculty are encouraged, but faculty are ineligible for the prizes.
For questions, comments or suggestions for future
challenge problems: please e-mail Ross McConnell, rmm@cs.colostate.edu.
