Solve for m:
Cross multiply: 
6m=8•12
6m=96
Divide both sides by 6: 
6m/6=96/6
m=16 
Substitute m=16 into the equation and check for proportionality: 
16/12=8/16
1/2=1/2 or .5=.5 
Therefore, because 6/12=1/2 and 8/12=1/2, they are equivalent fractions, meaning the quotient is the same. Because their quotients are constant (never varying), the two fractions are proportional. 
Answer: Fractions are proportional