tab offer odds of 3.6for melbourne to win with a margin btw...

tab offer odds of 3.6

for melbourne to win with a margin btw 1-12

the calculated odds for melbourne to win was $1.85 for at least 4point margin so can arbitrage that at $3.60

but only 54% success.
probably could use a kelly formula to size up ur bet.
input .54 for the probability
http://www.aussportsbetting.com/tools/online-calculators/kelly-criterion-calculator/

so for $500 bank roll using full kelly.
you could earn up to 36%
for a wager of
so around 181 bucks

and profit 171 bucks which is 94% return on the outlay.