Chi’s family has 5 people: grandfather; father; mother;  Chi and Hoang

Sunday morning the whole family likes to go to the circus, but only buy two tickets.

Everyone in the family to export 5 reviews:

- Chi and Hoang go- Grandfather and father go

- Mother and Hoang go- Hoang and father go

Finally everyone agreed with the proposal of the Chi because according to that proposal, each of the proposals of the other 4 are satisfied in part and denied in part.

Who did go to the circus ?