I'm not going to give you the answer, but I can try to help you. A common denominator, I think, is like when you try to find out the number they all multiply. Like, for example, 9. 1, 3, 9, etc. are numbers you can use to either multiply up to 9, or more than 9. I don't know if I even make sense. Just do a good amount of research.
Answer:
Option (4)
Step-by-step explanation:
D = {x| x is a whole number}
D = {1, 2, 3, 4..........}
E = {x | x is a perfect square between 1 and 9}
E = {4}
F = {x | x is an even number greater than 2 and less than 9}
F = {2, 4, 6, 8}
(E ∩ F) = Set of common numbers of E and F
= {4}
D ∩ (E ∩ F} = Set of common numbers in the sets of D and (E ∩ F)
= {4}
Therefore, Option (4) will be the answer.
Answer:
Step-by-step explanation:
3 ÷ 2 1/3
2 1/3 can be written as 
Now we divide 3 by 7/3
Now we flip the fraction 7/3 and multiply with 3
We cannot simplify it
So 9/7 is the final answer
