An Englishman, an American and a Sardarji

An Englishman, an American and a Sardarji are called upon to test a lie detector. The Englishman says: "I think I can empty 20 bottles of beer". BUZZZZZZ, goes the lie detector."Ok", he says, "10 bottles". And the machine is silent.
The American says: "I think I can eat 15 hamburgers". BUZZZZZZ, goes the lie detector."Allright, 8 hamburgers". And the machine's silent.
The Sardarji says: "I think...",BUZZZZZZ goes the machine.