Originally Posted by
Ganchrow
You take the product of the decimal odds.
Hence, true parlay odds on two bets at would be (1+100/110)*(1+10/110) ≈ .
True parlay odds on one bet at and another at would be (1+100/105)*(1+100/110) ≈ .
This means that when parlaying 2 teams at -110 for +260 you're actually getting each team at odds of about .
Similarly, when parlaying 3 teams at -110 for +600 you're actually getting each team at odds of about .
Books will frequently offer 2- and 3- team parlays ot odds of +260 (13:5) and +600 (6:1), respectively. This is a throwback to the old days when (apparently) calculators were hard to come by and weighted several tons each (most of that weight was of course due to the wise-crackin' Pterodactyl that provided the calculator its juice). It was easier for a book maker (or is his customers) to calculate payout amounts at 13:5 or 6:1 than at 2.6446:1 or 5.9579:1.