ITV boss Michael Grade risked angering viewers by claiming they should develop a sense of humour over its controversial TV quizzes.
One maths question on the late-night Make Your Play show proved so difficult that even an Oxford University maths professor was unable to solve it. The game asked viewers to add Two Pounds, 25p, £1.47, 16p and fifty pence.
No one won the £30,000 prize.
ITV revealed the answer to be 506p, but gave no explanation. It later released a highly complicated solution.
Asked about the quiz when he appeared before a committee of MPs on Tuesday, Mr Grade said: “The 506p question – I think we are in danger of losing our sense of humour.
“Whilst it may have taxed the odd scientist and mathematician, it was in fact no more than in the great tradition of cryptic questions.
“Viewers were told the answer wasn’t obvious and that it was cryptic.”
MP Philip Davies interjected: “Perhaps we can afford to keep a sense of humour because we weren’t conned into phoning up this programme.”
But Mr Grade insisted: “It’s a schoolboy riddle.”
When pressed on whether or not he thought the question acceptable, he replied: “In the context of a cryptic clue, absolutely.”