Reenster,

The dollar figures shown below the prices are the amount that is currently on offer (or being requested) at the given price. In the example you gave the $388 @ $6 means that someone is willing to accept up to $388 at that $6.00 price so you can bet up to that amount (so the figure given is the amount you can bet - not how much will be won). The good thing about Betfair is you can place a bet for a lesser or greater amount than what is on offer (I think Twoflys limits you to accepting specific bets - eg. if someone offers $50 on TwoFlys you either bet the full $50 or nothing - you cant take just $10 of it - I could be wrong however as I have not actually used TwoFlys). If you bet less than the amount on offer then your bet is "fully matched" and the amount on offer is decreased by that amount. If you want to bet more then the system will match what is available and then place an "order" for the remainder.

In your example if you bet $100 @ 6.00 then you would get your bet and the system would update to show $288 still available at $6.00. If you bet $500 @ $6.00 then the system would match the $388 currently available and the remining $112 would appear on the "lay" side at $6.00 showing that you are willing to accept up to $112 in bets at that $6.00 price.

The Lay side of things works the same way - the dollar value is the amount that people are wanting to bet at the specified price and you can match some, all or more than the specified amount (so to answer your question if you accepted the $122 at $7 lay then you would be liable to pay $122 x $7 if the horse won). If you are willing to accept more than the $122 again you can enter that and the system will match the $122 amount and display the remainder on the "bet" side showing that you are willing to take bets at the $7 price.

It can be a bit confusing at first so I suggest you start with a few small bets to get the hang of it. I made one mistake when I started and accidentally "layed" a selection at $7 instead of backing it - fortuately I was able to back it at the same price so I didn't lose any money. Once you get the hang of it though it is quite easy.

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"Computers can do that????" - Homer Simpson