Here is a list of all the Problems of the Month that have been posted from
January 2007 through December 2015.
You may view any of the past problems by clicking on the name.

2007

  Date   Name of Problem of the Month Math Needed
January 2007 Mr P's Life Algebra
January 2007 Carrie the Camel Arithmetic
           
February 2007 How Many Squares? Geometry
February 2007 How Fast Must I Go? Algebra
February 2007 How Much Homework? Algebra
           
March 2007 SUDORKU Calculus, Algebra, Geometry
March 2007 Fill in the Blanks Geometry, Arithmetic
March 2007 Change for your Dollar Arithmetic
           
April 2007 Mathematician's Puzzle Logic
April 2007 Coin Flipping Game Probability
April 2007 Sports Math Arithmetic, Algebra
           
May 2007 The Basement Problem Geometry
May 2007 High Schools in Fort Collins Algebra (Pascal's Triangle)
           
June 2007 My Mistake Logic
           
July 2007 Manhattan & the Indians Algebra
           
August 2007 Interstate Highway Trip Logic
           
September 2007 Famous Addresses None
September 2007 Leftovers Again? Number Theory
September 2007 Runner's Rate Algebra
           
October 2007 Allowance Problem Arithmetic, Logic
October 2007 Scrabble Comic Arithmetic, Logic
October 2007 Pumpkin Maze Logic
           
November 2007 Airport Problem Geometry, Logic
November 2007 Walking Problem Algebra
November 2007 Sum Problem Arithmetic, Logic
           
December 2007 Christmas Square Dance Algebra (Squares)
December 2007 Magic Square Algebra
December 2007 Train Message Algebra
           

2008

  Date   Name of Problem of the Month Math Needed
January 2008 Paper Problem Logic, Geometry
January 2008 Mathematical Wackie Wordies Logic
January 2008 Harry Potter Problem Denominate Numbers
           
February 2008 Phone Number Problem Algebra
February 2008 Phone Button Boggle None
February 2008 MaxMin Problem Number Theory
           
March 2008 Tip Problem Algebra
March 2008 4 Questions Problem Algebra
March 2008 Aces and Faces Problem Logic
           
April 2008 CiCi Pizza Problem Algebra
April 2008 15% Tip Problem Algebra
April 2008 Deathly Hallows Problem Geometry
           
May 2008 Apple Blossom Problem Geometry
May 2008 In the Land of the Truth-tellers and Liars Logic
           
June 2008 Coin Problem Algebra
           
July 2008 The Bike Problem Percents
           
August 2008 The Candle Problem Algebra
           
September 2008 Personal Telephone Numbers Algebra
September 2008 Star Sum Algebra
September 2008 Gas Problem Arithmetic
           
October 2008 Square Sums Algebra
October 2008 Centennial Problem Geometry
October 2008 Biggest Number Problem Arithmetic
           
November 2008 Area Problem Geometry
November 2008 Election Day Cryptarithm Arithmetic
November 2008 In the Cards Logic
           
December 2008 Addition Trick Logic, Algebra
December 2008 Candy Canes and Ornaments Logic
           

2009

  Date   Name of Problem of the Month Math Needed
January 2009 Dorm Problem Logic, Number Theory
January 2009 Marriage Problem Logic, Algebra
January 2009 Hand Bell Problem Logic
           
February 2009 Likes / Dislikes Problem Logic
February 2009 Lunch Hour Problem Arithmetic
February 2009 Painting Problem Algebra
           
March 2009 Harry Potter Cryptarithm Algebra
March 2009 Mr. P's Social Security Problem Algebra
March 2009 College Math Algebra
           
April 2009 Letter Problem Logic, Patterns
April 2009 Three Stop Metro Maze Logic
April 2009 KenDoku Addition, Logic
           
May 2009 Missing Number Problem Algebra
May 2009 Dragon Problem Logic
May 2009 Checkerboard Problem Logic
           
June 2009 Exceptional Numbers Logic
June 2009 Hockey Problem Logic
           
July 2009 Estate Problem Percent, Algebra
           
August 2009 Belly Dancer Problem Algebra
           
September 2009 Blip, Blop, Bleep Problem Logic
September 2009 Cross Number Puzzle Logic, Number Properties
September 2009 Random Walk Probability
           
October 2009 Doodle Code Logic, Algebra Properties
October 2009 Circular Reasoning Logic
October 2009 Counting Triangles Geometry, Logic
           
November 2009 Tax Problem Algebra
November 2009 Sudominoku Logic
November 2009 Word Ladders Logic and Vocabulary
           
December 2009 Holiday Greeting Algebra
December 2009 Numbers and Operations Algebra
December 2009 Sequence Problem Algebra
           

2010

  Date   Name of Problem of the Month Math Needed
January 2010 HDTV Problem Geometry, Algebra
January 2010 Sales Problem Algebra
January 2010 Gatecrasher Problem Statistics, Logic
           
February 2010 MPH Problem #1 Arithmetic, Algebra
February 2010 MPH Problem #2 Algebra
February 2010 National Parks Tour Logic
           
March 2010 Prius Problem #1 Algebra
March 2010 Prius Problem #2 Algebra
March 2010 Prius Problem #3 Algebra
           
April 2010 Age Problem Arithmetic
April 2010 Applebee's Trios Problem Probability
April 2010 Number Trivia Arithmetic, Magic Squares
           
May 2010 Game of Fifty Arithmetic, Logic
May 2010 Four By Four Algebra
           
June 2010 Wal Mart Ad Arithmetic, Logic
           
July 2010 Bridge Problem Logic
           
August 2010 Math Facts Facts
August 2010 Heat Index Algebra, Matrices
           
September 2010 Humidifier Problem Algebra
September 2010 Crossword Sudoku Logic
September 2010 Mr. P's Life Algebra, Logic
           
October 2010 Clock Problem Algebra
October 2010 Scrabble Problem Geometry, Logic
October 2010 Going to St. Ives Logic
           
November 2010 Japanese License Plates Probabilty, Logic
November 2010 True or False? Logic
November 2010 IRA RMD Problem Algebra
           
December 2010 Double Sixes Probabilty
December 2010 Pedometer Problem Algebra
December 2010 Whiskeytown Lake Problem Algebra, Geometry
           

2011

  Date   Name of Problem of the Month Math Needed
January 2011 Crater Lake Problem Geometry, Algebra
January 2011 Counting Carbs Algebra
January 2011 Letters in a Square Logic
           
February 2011 Tuition Increase Algebra
February 2011 2011 Prime Problem Algebra
February 2011 Push Up Problem Algebra
           
March 2011 Addition Problem Algebra
March 2011 Carton Problem Algebra
March 2011 Push Up Problem -- Part Two Algebra
           
April 2011 Digit Problem Algebra
April 2011 Construction Problem Algebra
April 2011 Book Problem Logic
           
May 2011 Pond Problem Algebra, Geometry
May 2011 Sequence Problem Logic
May 2011 Lyin' Lonnie Logic
           
June 2011 Sum Triangle Problem Logic, Algebra
June 2011 Jackson's Age Algebra
June 2011 Mother & Daughter Problem Algebra
           
July 2011 Safe Deposit Box Problem Algebra
July 2011 Age Problem Algebra
July 2011 Sequence Problem Algebra
           
August 2011 Hiking Problem Algebra
August 2011 Money Problem Algebra
August 2011 Sonic Ad Problem Probability
           
September 2011 How Many Games? Logic, Primes
September 2011 CalcuDoku Logic
September 2011 Pencil Problem Algebra
           
October 2011 The Math Path Logic
October 2011 The Math Square Geometry
October 2011 The Bug Problem Algebra
           
November 2011 Set the Clock Back! Logic
November 2011 11/11/11 Problem Algebra
November 2011 Ranked Voting Problem Algebra, Logic
           
December 2011 Birthday Problem Logic
December 2011 Romeo and Juliet Arithmetic
December 2011 Good bye to 2011 Algebra

2012

  Date   Name of Problem of the Month Math Needed
January 2012 Credit Card Rewards Problem Algebra
January 2012 Upside Down Problem Algebra
January 2012 What Time Is It? Geometry
           
February 2012 Money Problem Logic
February 2012 Cross Math Problem Algebra
February 2012 Armadillo Restaurant Problem Algebra
           
March 2012 Divide and Conquer Algebra, Divisibilty
March 2012 Squares Away Arithmetic
March 2012 Mazematics Arithmetic and logic
           
April 2012 Sum Problem Arithmetic and logic
April 2012 Ultra-High Definition TV Problem Geometry
April 2012 Box Problem Logic
           
May 2012 Number Mazes Arithmetic and logic
May 2012 Geometry Cross Sum Arithmetic and logic
May 2012 The Puzzled Driver Logic, Algebra
           
June 2012 The Lady and the Tiger Arithmetic, Geometry
           
July 2012 Trains Meeting Algebra
July 2012 Round Table Logic
July 2012 Change the Equation Algebra, Logic
           
August 2012 Count the Triangles Arithmetic, Geometry
August 2012 Hardware Problem Algebra
August 2012 Clock Problem Algebra
           
September 2012 From Fort Collins to Rock Springs Algebra
September 2012 Matching Socks Probability
September 2012 Mulch Problem Logic, Arithmetic
           
October 2012 MONSTER COSTUME PARTY Logic
October 2012 Area Problem Geometry
October 2012 Tipping Problem Algebra
           
November 2012 Answering Machine Problem Arithmetic
November 2012 Restaurant Problem Logic
November 2012 Mr. P's age Logic, Arithmetic
           
December 2012 Tree Trimming Problem Logic
December 2012 Decode the Message Algebra, Trig, Calculus
December 2012 Reindeer and Sleighs Logic
           

2013

  Date   Name of Problem of the Month Math Needed
January 2013 The New Year Challenge Algebra
January 2013 Elvis, The King of Rock N Roll Logic, Arithmetic
January 2013 On The Level Logic, Algebra
           
February 2013 Equation Sudoku Arithmetic, Logic
February 2013 Ski Boot Sale Logic
February 2013 Homework Problem Arithmetic
           
March 2013 Wordoku Logic
March 2013 Coin Problem Arithmetic, Logic
March 2013 Rectangle Problem Geometry
           
April 2013 Tangent Circles Geometry
April 2013 Whale of a Tail Algebra
April 2013 Fraction Problem Arithmetic
           
May 2013 Three Circle Problem Geometry
May 2013 Mr. P's Garden Trigonometry
May 2013 Sum-Thing Missing Algebra, Logic
           
June 2013 Archery Problem Arithmetic
June 2013 Addition Problem Arithmetic, Logic
June 2013 Powerful Discovery Problem Arithmetic, Logic
           
July 2013 Have Sum Fun Logic, Arithmetic
July 2013 Square Deal Logic, Arithmetic
July 2013 Internet Problem Logic
           
August 2013 Sleepless in Fort Collins Arithmetic, Logic
August 2013 Try Angles Geometry, Logic
August 2013 Texting While Driving Algebra
           
September 2013 Best Chocolate Chip Cookie Logic
September 2013 Computer Passwords Probability & Statistics
September 2013 Tipping Problem Arithmetic, Logic
           
October 2013 Clueless Crossword Logic
October 2013 Jackpot Yahtzee Probability & Statistics
October 2013 Incline Railway Geoometry or Trigonometry
           
November 2013 KenKen Puzzle Logic, Arithmetic
November 2013 Birthday Problem Probability
November 2013 Wheel of Math Logic
           
December 2013 Birthday Problem Revisited Probability
December 2013 Circle / Triangle Problem Geometry
December 2013 The Game of Kayles Logic
           

2014

  Date   Name of Problem of the Month Math Needed
January 2014 The New Year Challenge Algebra
January 2014 Cross Out Arithmetic, Logic
January 2014 National Park Road Kill Arithmetic, Algebra
           
February 2014 Hobo Problem Algebra
February 2014 Contracting Costs Algebra
February 2014 Tipping Problem Algebra
           
March 2014 Travel Problem Algebra
March 2014 Inferno Algebra
March 2014 Trivia Magic Square Algebra, Geometry
           
April 2014 Poker Squares Logic
April 2014 State Capitals Tour Logic
April 2014 Algebra Limericks Algebra
           
May 2014 Jack and Jill Algebra
May 2014 Metroville Logic
May 2014 Checkerboard Problem Logic, Patterns
May 2014 Handley High Adventure ($100 prize) Logic
           
June 2014 Odd Day Problem Arithmetic
June 2014 CSU Basketball Problem Arithmetic
June 2014 Euclid's Problem Algebra
           
July 2014 Billion Dollar Money Problem Arithmetic
July 2014 Strange Game Arithmetic, Logic
July 2014 Brick by Brick Geometry, Logic
           
August 2014 Special Numbers Problem Arithmetic, Logic
August 2014 99 Bottles of Beer Arithmetic, Logic
August 2014 Baseball Problem Logic
           
September 2014 A Madam Problem Logic
September 2014 Football Attendance Problem Algebra
September 2014 Chess Problem Algebra
September 2014 States Trivia Game Logic
           
October 2014 Balance Quest Algebra, Logic
October 2014 Square Abouts Logic
October 2014 Flipping Pancakes Logic
           
November 2014 Rhyme Time Logic
November 2014 Ice Explorer Problem Logic
November 2014 Calgary Tower Problem Logic
           
December 2014 Christmas Tree Problem Logic, geometry
December 2014 Prime Interest Logic, Primes
December 2014 Coke Zero Problem Arithmetic

2015

  Date   Name of Problem of the Month Math Needed
January 2015 The New Year Challenge Algebra
January 2015 Markdowns or Freebies? Arithmetic
January 2015 Trial Separation Logic, Geometry
           
February 2015 Valentine's Message Arithmetic
February 2015 Clock Problem Geometry, Logic
February 2015 HDTV Problem Geometry, Algebra
           
March 2015 Easy As 1, 2, 3 ... Arithmetic, Logic
March 2015 Celebrity & Real People Salaries Arithmetic
March 2015 A Square Deal Arithmetic, Logic
           
April 2015 Coke Zero Part 2 Arithmetic
April 2015 Math Maze Arithmetic, Logic
April 2015 The Wheel Thing Algebra
           
May 2015 Number Play Arithmetic, Algebra
May 2015 ISBN Problem Arithmetic
May 2015 Easy as A,B,C Arithmetic
           
June 2015 Anniversary Message Arithmetic, Logic
June 2015 Sum-Thing Missing Arithmetic, Logic
June 2015 The Wading Pool Arithmetic, Logic
           
July 2015 Parking Lot Problem Logic
July 2015 Pipe Problem Logic
July 2015 Circle Problem Logic
           
August 2015 Widget Digits Arithmetic, Logic
August 2015 Shapes Puzzle Logic
August 2015 Tic Tac Toe Triple Play Logic
           
September 2015 What's A Name In? Logic
September 2015 Card Trick Arithmetic, Logic
September 2015 Mr. P's Grandchildren Logic
           
October 2015 Birthday Problem Logic
October 2015 Word Worms Logic
October 2015 SPOT IT! Logic
           
November 2015 Mathematical Road Trip Logic
November 2015 Small Change Logic
November 2015 Odd Letter Out Logic
           
December 2015 A Number and its Reciprocal Algebra
December 2015 Mr. P in the Prime of his Life Algebra
December 2015 Logical Sequences Algebra