by John Ehrke | Oct 5, 2018 | Problem of the Week
How Many Words? This problem is from Matt Compton, University of Oklahoma. How many five-letter strings can be formed using the 26 (upper case) letters of the alphabet, subject only to the restriction that consonants cannot be next to each other and likewise vowels...
by John Ehrke | Sep 28, 2018 | Problem of the Week
Two Boats on a River This problem is from Joe Black, Athens, Texas, by way of Marilyn vos Savant, Parade Magazine. Two motorboats at opposite shores of a river start moving toward each other at constant, but different, speeds. (Neglect all other factors, like...
by John Ehrke | Sep 21, 2018 | Problem of the Week
Arithmetic Border for a Square This problem is from Grant Fikes. Fill in integers in the table below so that each row and each column of the border of the square is an arithmetic sequence. Note: The incremental change may be different for each of the four sequences....
by John Ehrke | Sep 14, 2018 | Problem of the Week
The Probability Both Roots are Positive and Real This problem is from Gary Gordon, Lafayette College Let f(x) = x2 + bx + c where b and c are real numbers between -1 and 1. What is the probability that both roots of f(x) are positive real numbers? Submit your answers...
by John Ehrke | Sep 8, 2018 | Problem of the Week
What Were the Correct Answers? This problem is from Tamar Malinek, by way of Marilyn vos Savant, Sunday Parade Magazine (Abilene Reporter News.) Mrs. Smith, a teacher, gave five students a make-up science test. There were five questions on the test. However after...
by John Ehrke | Aug 28, 2018 | Problem of the Week
Background The POTW competition has existed in form or another since September 3, 1990, when the first problem was given by Dr. Bo Green, professor emeritus of the Department of Mathematics until his retirement in 2009. The competition was excitedly restarted in Fall...
