In this post we will resolve the OBMEP 2018 questions with comments. Question 1 A crazy machine turns two fruits into one fruit, as follows: Turns two apples into an orange; Turns two oranges into one orange; Turns an apple and an orange into an apple. Q1 Item a a) How many times should the machine be used to turn three apples into one apple? Data: Initially we have 3 apples.