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theMusicMan
24th December 2007, 12:26 AM
Had a great evening tonight; watched a film, then at around 09:30 the TV went off and Jen (my wife), my lad Lloyd (17) and my Sister in law Lynda sat and conversed until 10 mins ago - talking all manner of things. What a great evening...

One subject that came up was a question that apparently was asked on last weeks 'Are you Smarter than a 10 year old" show. Lynda mentioned that the question, the topic of which was maths, that the adult got it wrong and the 10 year old got it right. A great debate in our household ensured....

The question was... "What is 5 + 3 x 0 ?"

The lady on the show had answered... 8 - which is of course, very wrong. I said what I said was the right answer, and my Sister in law said that the answer I gave was not the so called 'correct' answer that was provided on the show - which the 10 year old gave as their answer.

The 'correct' answer as given on the show was - 0. I would say that the correct answer was 5. What would you say...?

Curiously, I tried this in calculator on my PC, and on my Mac.

Calculator on PC (XP SP2) says; 0
Calculator on Mac (OSX 1.5) says the correct answer: 5

How you....? Surely the correct answer is 5...??

dlinney
24th December 2007, 12:30 AM
Its a matter of convention. There is no correct answer.

If you apply all operators as being of equal precendence and evaluate left to right the answer is 0.

If you apply precendence to operators (as all computer programs and spreadsheets do) then the multiply operator has higher precedence than the addition operator so the answer is 5.

theMusicMan
24th December 2007, 12:31 AM
But Derek, if you apply the laws of maths, simple algebra, the answer is 5. It's not about convention!

EDIT: you also mention that "all computers do" - try this using Calculator on a PC and the answer given is 0, whereas on my Mac, the answer given is 5.

Andrew Riddell
24th December 2007, 01:31 AM
Surely this depends on whether you are interpreting the formula as:

(5 + 3) x 0 = 0; or

5 + (3 x 0) = 5

If you do not use the brackets, you will get the first answer, because none of the numbers are linked as a first stage calculation.

I can see this discussion running over many pints, even on Christmas Eve! Enjoy!

Andrew

PeterD
24th December 2007, 05:20 AM
Surely this depends on whether you are interpreting the formula as:

(5 + 3) x 0 = 0; or

5 + (3 x 0) = 5

If you do not use the brackets, you will get the first answer, because none of the numbers are linked as a first stage calculation.

I can see this discussion running over many pints, even on Christmas Eve! Enjoy!

Andrew

The golden rule here is BODMAS - Brackets off, Divide, Multiply, Add, Subtract.

The expression as written does not have any brackets nor any division. The answer must therefore be 5.

To answer any mathmatical question the expression must be precise. Forgetting brackets to group expressions will always result in an imprecise result.

PeterD

sapper
24th December 2007, 08:55 AM
The mind boggles!!
:-)
Dave

theMusicMan
24th December 2007, 09:30 AM
Spot on PeterD - this is exactly the reason I said 5 as my answer. The rule of BODMAS doesn't apply when you're 11 and not when you're 10!! So, in my opinion, the show got it totally wrong and should be brought to task over it.

One always carries out multiplication and division before addition and subtraction. :)

PeterD
24th December 2007, 09:49 AM
Spot on PeterD - this is exactly the reason I said 5 as my answer. The rule of BODMAS doesn't apply when you're 11 and not when you're 10!! So, in my opinion, the show got it totally wrong and should be brought to task over it.

One always carries out multiplication and division before addition and subtraction. :)

Perhaps I am showing my age:o We learnt BODMAS before going to secondary school! I thought standards had slipped, now I know.

Kind regards

PeterD

Rod Souter
24th December 2007, 09:02 PM
I think it is 5!

http://www.webopedia.com/TERM/p/precedence.htm


Rod

flying haggis
24th December 2007, 10:46 PM
for f*cks sake go to bed

does it matter anyway!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Rod Souter
25th December 2007, 03:19 PM
Yes
:D:D:D:D

Rod