Answer:
[tex]\frac{8}{11}[/tex]
Step-by-step explanation:
Since the fractions are like, their denominators are 11, then
consider the values that sum to give 18 , that is
1 + 9 + ? = 18
10 + ? = 18 ( subtract 10 from both sides )
? = 8
Then the third fraction is [tex]\frac{8}{11}[/tex]