aµdt = hµcµdt = average probability that a reaction Rµ will occur in the next time interval dt
Cµdt = average probability that two reactant molecules will collide according to Rµ in the time interval dt
hµ = total number of possible reaction combinations
e.g: Homocysteine conversion to metheonine is reaction six (R6):
R6: Five MTHF+Hcy→THF+Met
Assuming there is Z molecules of five MTHF
 X molecules of Hcy:
h1 = X*Z = number of possible reaction combinations
X*Z* C6dt = Probability that R6 will occur inthe next time interval.
Where C6 is the stochastic rate constant for reaction 6
Table 3: Example of a Stochastic Reaction.