##4 languages, 24 bytes, 24/4^3=0.375
 print(1//0.5--1+1/2*2
 );
##1. PHP
PHP executes `print(1);` which equals 1
##2. Lua
Lua executes `print(1//0.5);` which equals 2
##3. Python 2
Python 2 executes `print(1//0.5--1+1/2*2);` which equals 3 (integer division)
##4. Python 3
Python 3 executes `print(1//0.5--1+1/2*2);` which equals 4 (float division)