It don't works:
Error:
'{_kap.%victim%} / 10 money' can't be added to an entity because the former is neither an item type, an inventory nor an experience point
code_language.skript:
on death of player:
set {_bal.%victim%} to victim's balance
set {_kap.%victim%} to ({_bal.%victim%} / 10) * 2
if attacker is a player:
give {_kap.%victim%} money to attacker
Error:
'{_kap.%victim%} / 10 money' can't be added to an entity because the former is neither an item type, an inventory nor an experience point