An old man walks into a bar and slams a bag of gold coins down, addresses the customers by saying,
“I’ll give this entire bag of coins to any man here able to drink 10 pints in 2 minutes’”
Nobody takes him up on the offer but he notices an Irishman getting up and leaving.
A few minutes later the Irishman is back and says to him,
“Is yer wager still applicable.”
The old man tells him it is and the bartender sets 10 pints of ale on the bar.
In a minute and a half flat, the Irishman is done and the old man hands him the bag of money.
“Just one thing sir”, the Old man says,
“I noticed you left the pub earlier when I introduced my proposal.”
“Aye ye did see,” says the Irishman,
“I went next door to see if I could do it first”.