Go half and half
Definition 1 of 1
Pro Tip 1/3Equal Partnership
The phrase indicates a joint venture where each person has equal stake or responsibility. 
We decided to go half and half on our science fair project.
Pro Tip 2/3Casual Finance
Mostly used in informal financial contexts among friends or colleagues, not in official business dealings. 
For our road trip, shall we go half and half on gas and snacks?
Pro Tip 3/3Friendship Gesture
Suggesting to 'go half and half' can show fairness and goodwill in a friendship or close relationship. 
We both love this video game, so let's go half and half on it!