Problem C. 1252. (November 2014)
C. 1252. The product of four consecutive odd numbers ends in 9. What may be the digit preceding the 9 in the product?
(Matlap, Cluj)
(5 pont)
Deadline expired on December 10, 2014.
Statistics:
188 students sent a solution. 5 points: 103 students. 4 points: 16 students. 3 points: 17 students. 2 points: 20 students. 1 point: 19 students. 0 point: 3 students. Unfair, not evaluated: 10 solutionss.
Problems in Mathematics of KöMaL, November 2014