Math question on calculating stake/liability

[Datapunter]

This is doing my head in as i just can't seem to work it out. I have a bet at a bookie for 25 @ 2.30 which is a free bet, stake not returned, so if it wins you only get the profit being 32.5 I want to cover this bet by laying at an exchange and thus securing a profit both ways. Lay odds are 2.30 with 5% commission. (but odds are usually a little bigger say 2.35 ) Now i know that i need to Lay 14.44 for a liability of 18.78 ( as there's a site with a calculator that tells me this :D ) How the f*** do you work it out ? I'll spell it out first: winning at the bookie: 25 @ 2.30 gives 32.5 profit when winning at the bookie, minus the liability at the exchange -18.78 is an actual profit of 13.72 winning at the exchange: 14.44 @ 2.30 gives (-5%) 13.72 profit if winning at the exchange side, no loss at the bookie as that is a free bet anyhow so actual profit 13.72 So either way the actual profit is the same: 13.72 How do i work out the 14.44 so i get equal profit either way ?????????

[melcon]

Re: Math question on calculating stake/liability Hi datapunter: you want to equal both sides: winning at bookie stake bookie * 1.3 - Liab *1.3 winning at exchange liab * 0.95 so stake b * 1.3 - liab *1.3 = liab *0.95 ==> stake b * (1.3) = liab * (0.95 +1.3) ==> stake b * ( 1.3 / 2.25) = liab stake b is 25 in your case so liab = 25 * 1.3/2.25 = 14.44 hope that helps melcon