We have been that Arelli drank 2/3 liter of water Monday before going jogging. She drank 5/7 liter of water after her jog. We are asked to find the amount of water that Arelli drink altogether.
To find the amount of water that Arelli drink altogether, we will add amounts of water drank before going to jogging and after the jogging.

Let us make a common denominator.


Now we will combine numerators.



Therefore, Arelli drank
liters of water altogether.