Answer:
3
Explanation:
first put them in order
1 1 2 3 3 4 5
then cancel them down go from the front to the back so go like
1 then 5 then 1 again then 4 and etc
u would then end up with the last two numbers which is 3 and 3. if u had numbers like 5 and 7 u would have to find the number in the middle of which would be 6. in the case the two numbers you are left with is 3 and 3 since there both the same the answer would be 3
hope this helped :)