Daily Mini-Quiz
10:17 UK time, Tuesday, 13 March 2007
Monday's Daily Mini-Quiz set a question that had originally appeard on ITV's Make Your Play (with a £30,000 prize) which no one had managed to answer correctly.
"Add the pence - two pounds, 25p, £1.47, 16p, fifty pence". Just 8% of our respondents got ITV's official answer 506. But since the broadcaster had offered no explanation of how it got to the sum we asked readers to come up with suggestions.
Thanks to all those who sent in explanations, including:
Mike Rochford, Hull - "Interestingly, if you divide the prize money of £30,000 by the answer which appears to be the correct one: 438 you get 68, and if you add those two figures together it equals the answer they claim: 506."
Robert L James, who embarked on a route that required weighing the pennies (see below for a full explanation)
Dr. Mike Goldfinch, who thought "the solution is to interpret p as new pence and the word pence as old pence", and
Ian Brennan, who put it all down to a colour order of some sort.
Congratulations to James Cofone, Paul Appleby, Chris Appleyard, Dr. Tom Brownlee and Chris Blocksidge of Stuttgart - "We have these quizshows in Germany too" - who were among those thinking along the same lines as ITV - the channel did, on Monday, release an explanation.
James Cofone explains it thus:
Ok first add everything. £2 + 25p + £1.47 + 16 + 50 = 438.
Now add the other sums which are visible. 5p (from the 25p) + 47p (from £1.47) + 7p (again from £1.47) + 6p = 65p
Therefore 438 + 65 = 503.
Now add the 'p' from 25p and 16p and also the 'pence' from 50 pence giving an extra 3p.
Therefore 503 + 3 = 506p.
"But that’s ever so slightly cheeky. I think a better question is 'how do they get away with this?'," says James.
Meanwhile, here is Robert L Jame's alternative theory:
Add together the amounts of actual money:
25p + £1.47 + 16p + fifty pence = 228p
Now, suppose the 'two pounds' is two pounds weight of pennies.
New pennies weigh 3.56g when minted
(source).
Two pounds in grams is 907.18474 (source Google conversions)
907.18474/3.56 = 255 (rounded up to nearest whole coin).
228 + 255 = 483
which is close to 506 (-23).
If the count of pennies in two pounds was done empirically by weighing pennies on a scale, then the fact that many of them could have been worn, thus reducing their weight, and the scale may not have been accurately calibrated, might account for the discrepancy.
It is an approximate 10% margin of error which may, or may not, be considered reasonable.
(It's also possible that somebody couldn't count - and it wasn't in their interest to use somebody who could).
In light of the margin for error, I'd be happy to settle for 90% of the original prize money.
The 
