Nope, well, not really... The bypass ratio is just that, in your example there will be 5x volume of air coming from the fan for every 1x volume coming from the turbine.
The typical high-bypass turbofan gets about 80% of it's thrust from the fan at take off.
A relation does exist, but it won't be directly proportional, won't be constant, and will depend on things like number of stages of compression, number of spools, number of stages of turbine etc.
Cheers.