The Americans Challenge

A rich American challenged An Englishman, an Irishman and a Scotsman to drink ten pints of Guinness in ten minutes.
The Englishman tried but could manage only five pints.
The Scotsman did a bit better - he drank seven pints in ten minutes.
The Irishman downed The ten pints in nine minutes and as The American handed over The prize money he remarked. 'I didn't think you could do it.'
'I knew I could,' said The Irishman, 'because I did The same thing in The pub next door a few minutes ago.'