ITV was embarrassed yesterday into revealing how to answer a £30,000 late-night maths quiz problem that nobody — including Oxford University’s Professor of Mathematics — seemed able to solve.

Viewers of Make Your Play, which appeared on ITV on February 22, were asked: “Add the pence, listed: Two pounds, 25p, £1.47, 16p and fifty pence.” A prize of £30,000 was on offer, but calls were charged at 75p a time.

Later that night, the answer was given as 506, although simple addition produces the answer 438.

ITV explained that the answer could be reached by breaking up the figures in the list to find all the references to pence. Thus:

-Two pounds is 200p plus 2p (two p) and 1p (p at the beginning of “pounds”) which makes 203p

-25p: 25p plus 5p and 1p (the p symbol) = 31p £1.47 = 147p 1

-6p: 16p plus 6p and 1p (p again) = 23p

-Fifty pence: 50p plus 50p (fifty p, a shortening of pence), 1p (reference to pence) and 1p (p only) = 102p

-Adding 203p, 31p, 147p, 23p and 102p gives a total of 506p

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