Answer:
Pour 7 times
Step-by-step explanation:
In order to get 3 equal volumes when starting with a 9L jug, each volume must be 3L.
1) Pour from the 9L into the 5L
2) Pour from the 5L into the 2L (resulting in 3L leftover in the 5L jug)
Now we have 1 jug of 3L
3) Pour the 3L from the 5L jug into the 4L jug (to get it out of the way)
4) Pour the water from the 2L back into the 9L jug (which is now 6L fill)
5) Pour water from the 9L jug into the 5L jug
6) Pour from the 5L jug into the 2L jug resulting in 3L leftover in the 5L jug
Now we have 2 jugs of 3L
7) Pour water from the 2L jug into the 9L jug which has 1 L of water in it.
Congratulations you now have 3 jugs, 3L each.