average odds

and how on total goals markets are prices sometimes for example 67.34, or 99.12?

well in any market, to win markets if you have matched a lay at 12.5 and the same selection 1.05 wats the average matched?

d1 to a 1 units stake, assuming bf style odds
d2 to a 1 units stake, assuming bf style odds

Therefore you get back
(d1+d2) to a 2 units stake

Therefore your average odds are:
(d1+d2)/2

Hi Trader Pj. thanks for your help, i was working out the same but for some reason according to betfair is not right,
12.5+1.05 equal 13.55/2 equal 6.77 average matched know betfair is 7.51 what im missing here?