Universally challenged

I gave some incorrect answers on the two occasions I was on University Challenge, including one to a geological* question, but I never said anything quite as daft as this:

Jezza Paxo: Who was Prime Minister of the UK when current Prime Minister Dilbert Macaroon was born?

Warwick University student: Margaret Thatcher.

Between 22 and 33 years of age, according to the above logic.

Private Eye would be proud.

*I said Thalassia was the ocean that surrounded Pangaea, but I was wrong.