They also can stack. So a real-time coin game is 50% x 150% = 75%

And I was like...why am I getting only 50% everytime.

"The number of players who didn't win the game. Winning a 3-player FFA gives (on average) twice as many points as a 1v1, since there were two losers as opposed to one. Likewise, winning a 20 player FFA gives 19 times as many points as a 1v1.
The levels of the players who didn't win the game. Defeating a player who is equal level to you gives a base of 5,000 points. Defeating a player who is 10 or more levels above you gives a base of 10,000 points. Defeating a player who is lower level than you gives fewer than 5,000 points, depending on their level.
If the winning player is over level 8, their points are also affected by how recently they've defeated this player before. Defeating the same player twice in a 10-day period reduces the points earned from that player by 50%. Defeating the same player three or more times in a 10-day period reduces the points earned from that player by 80%.
In team games, the team essentially splits the points earned from the defeated players. However, team members can also receive different amounts of points due to the above rules (if the team members are different levels or have defeated some of the opponents recently.)"

Just copied this from the wz wiki

Any reason for this? or is it Random?