$2+4+6+8+9+11=40$  $2$ groups: sum of each group is $20$, $20=9+11=2+4+6+8$ 
The numbers $$2$$, $$4$$, $$6$$, $$8$$, $$9$$ and $$11$$ are divided into groups of one or more numbers. The sum of the numbers in each group is the same. Which number must be in the group with the number $$11$$? 
Options:
a. $$2$$ 
b. $$4$$ 
c. $$6$$ 
d. $$8$$ 
e. $$9$$ 