17). Each number is changed by the same rule inside this number changer. Given these four numbers and their result, find the rule.




Answer:____________

18). You are a spy trying to break an enemy code. You broke into their computer and found these equations:
3&5 = 14, 1&4 = 7, 6&3 = 21. What is 2&12?


Answer:____________

19). If 1@3 = 6 and 7@4 = 25 and 5@8 = 23, what is 12@11?

Answer:____________