Le Stu Posted April 12, 2011 Author Report Share Posted April 12, 2011 There's a guy at Aberdeen College that loves his calculators. Forgot his name but he's a legend when it comes to maths. You'll know who I'm on about.I'll keep an eye out for him Quote Link to comment Share on other sites More sharing options...
Alkaline Posted April 12, 2011 Report Share Posted April 12, 2011 What the fuck is going on here? Piss of with your arithmetic. Dicks. Quote Link to comment Share on other sites More sharing options...
Le Stu Posted April 12, 2011 Author Report Share Posted April 12, 2011 What the fuck is going on here? Piss of with your arithmetic. Dicks.that's more trolling maths, rather than maths trolling.(one for the right-brained amongst us.) Quote Link to comment Share on other sites More sharing options...
Alkaline Posted April 12, 2011 Report Share Posted April 12, 2011 that's more trolling maths, rather than maths trolling.(one for the right-brained amongst us.)Nice spot. Quote Link to comment Share on other sites More sharing options...
keeno Posted April 12, 2011 Report Share Posted April 12, 2011 There's a guy at Aberdeen College that loves his calculators. Forgot his name but he's a legend when it comes to maths. You'll know who I'm on about.The head of the maths department at the school I went to wrote programmes for graphical calculators. Had a holster on his belt for calculators and everythingCalculator Software .co.uk - About the TI Software and its DesignerExtremely nerdy but also thoroughly nice chap. He loved Blackadder, nuff said.Graphical calculators are ACE. I used to sit in Maths classes playing poker. Quote Link to comment Share on other sites More sharing options...
Hugh_Jazz Posted April 12, 2011 Report Share Posted April 12, 2011 It's 288.BODMAS.....brackets, orders, division, mult, add, subtract48/2(9+3)This is the same as saying 48/2*(9+3)So, first expand the brackets:48/2*12Division takes precedence over multiplication so, next divide 48 by 2:24 * 12Last do the multiplication.....288.It is absolutely not 2! Quote Link to comment Share on other sites More sharing options...
Alkaline Posted April 12, 2011 Report Share Posted April 12, 2011 48/2*12Surely that would have to be (48/2)*(9+3) for that to work? Quote Link to comment Share on other sites More sharing options...
Le Stu Posted April 12, 2011 Author Report Share Posted April 12, 2011 It's 288.BODMAS.....brackets, orders, division, mult, add, subtract48/2(9+3)This is the same as saying 48/2*(9+3)So, first expand the brackets:48/2*12Division takes precedence over multiplication so, next divide 48 by 2:24 * 12Last do the multiplication.....288.It is absolutely not 2!You can also expand the brackets as:48 / 2(9+3)48 / 18 + 68.67 (to 2dp) Quote Link to comment Share on other sites More sharing options...
Hugh_Jazz Posted April 12, 2011 Report Share Posted April 12, 2011 Surely that would have to be (48/2)*(9+3) for that to work?No, you dont need the extra brackets. . In the absence of brackets, division comes before mult, so you should always do 48/2, before 2*12.Just follow the precedence rules! Quote Link to comment Share on other sites More sharing options...
Oedo 808 Posted April 12, 2011 Report Share Posted April 12, 2011 Hey guys, I've solved this one.It's 2. Quote Link to comment Share on other sites More sharing options...
Captain America Posted April 12, 2011 Report Share Posted April 12, 2011 No, you dont need the extra brackets. . In the absence of brackets, division comes before mult, so you should always do 48/2, before 2*12.Just follow the precedence rules!Multiplication and division are inverse functions of each other. They actually have the same importance which is another reason this causes confusion, Quote Link to comment Share on other sites More sharing options...
soundian Posted April 12, 2011 Report Share Posted April 12, 2011 482(9+3) ? I make it equal to 'F' for fail. As pointed out division and multiplication are of equal weighting so you do not have enough information to do anything other than take a guess at which way the person who wrote it means it to be. You can resolve it to: 48/2x12 but without extra parentheses you have no idea whether the denominator or the numerator is meant to include the 12. Quote Link to comment Share on other sites More sharing options...
Hugh_Jazz Posted April 12, 2011 Report Share Posted April 12, 2011 Multiplication and division are inverse functions of each other. They actually have the same importance which is another reason this causes confusion,....and it is exactly because they have equal importance that we need a convention that tells us how to evaluate ambiguous looking expressions in the correct order. That convention is BODMAS, and that requires you do the division first. Of course, the unambiguous way to do this is to use more brackets.....but in the absence of these brackets, you've got to follow the precedence rules.288. Quote Link to comment Share on other sites More sharing options...
soundian Posted April 12, 2011 Report Share Posted April 12, 2011 ....and it is exactly because they have equal importance that we need a convention that tells us how to evaluate ambiguous looking expressions in the correct order. That convention is BODMAS, and that requires you do the division first. Of course, the unambiguous way to do this is to use more brackets.....but in the absence of these brackets, you've got to follow the precedence rules.288. BODMAS=BOMDAS=BODMSA=BOMDSA Multiplication and division have the same weighting, addition and subtraction have the same weighting. Quote Link to comment Share on other sites More sharing options...
soundian Posted April 12, 2011 Report Share Posted April 12, 2011 You can also expand the brackets as:48 / 2(9+3)48 / 18 + 68.67 (to 2dp) You cant, you have to resolve what's in the brackets first. Quote Link to comment Share on other sites More sharing options...
Le Stu Posted April 12, 2011 Author Report Share Posted April 12, 2011 ....and it is exactly because they have equal importance that we need a convention that tells us how to evaluate ambiguous looking expressions in the correct order. That convention is BODMAS, and that requires you do the division first. Of course, the unambiguous way to do this is to use more brackets.....but in the absence of these brackets, you've got to follow the precedence rules.288.ah, but 2(9+3) isn't 2*(9+3), it's ((2*9)+(2*3))makes more sense if you use x= 2x(9+3) = 9x+3x = 12x = 12*2 = 24.If it was explicitly 2*(9+3) rather than 2(9+3) then that would be a different matter. This is a confusion of notation. Quote Link to comment Share on other sites More sharing options...
fatboy Posted April 12, 2011 Report Share Posted April 12, 2011 Holy shit why? Quote Link to comment Share on other sites More sharing options...
fatboy Posted April 12, 2011 Report Share Posted April 12, 2011 plus 1 on the bracketsgot told that's why they are in brackets so you know to do it first rather than doing what is the normbread and butter maths as Mrs Shand used to say Quote Link to comment Share on other sites More sharing options...
soundian Posted April 12, 2011 Report Share Posted April 12, 2011 ah, but 2(9+3) isn't 2*(9+3), it's ((2*9)+(2*3))makes more sense if you use x= 2x(9+3) = 9x+3x = 12x = 12*2 = 24.If it was explicitly 2*(9+3) rather than 2(9+3) then that would be a different matter. This is a confusion of notation. You've multiplied first, then resolved the brackets. This is wrong. You know it is. Quote Link to comment Share on other sites More sharing options...
Le Stu Posted April 12, 2011 Author Report Share Posted April 12, 2011 You cant, you have to resolve what's in the brackets first.Well, I guess you could do that, so you get 2(12), which expands to 24. Same difference. You have to expand the brackets first, as per BODMAS. Quote Link to comment Share on other sites More sharing options...
soundian Posted April 12, 2011 Report Share Posted April 12, 2011 Well, I guess you could do that, so you get 2(12), which expands to 24. Same difference. You have to expand the brackets first, as per BODMAS. Yeah, but is it: 48----- (9+3)2or48-----2(9+3)Without extra parentheses both are equally valid. Quote Link to comment Share on other sites More sharing options...
Le Stu Posted April 12, 2011 Author Report Share Posted April 12, 2011 You've multiplied first, then resolved the brackets. This is wrong. You know it is.No, it's fine. substitute x for 2:x(9+3) 9x+3x12xOrx(9+3)x(12)12xdoesn't matter. Quote Link to comment Share on other sites More sharing options...
Le Stu Posted April 12, 2011 Author Report Share Posted April 12, 2011 Yeah, but is it: 48----- (9+3)2or48-----2(9+3)Without parentheses both are equally valid.The latter as 2(9+3) is a natural expression. It isn't 2*(9+3). Quote Link to comment Share on other sites More sharing options...
soundian Posted April 12, 2011 Report Share Posted April 12, 2011 The latter as 2(9+3) is a natural expression. It isn't 2*(9+3). They're exactly the same thing. You could call it laziness but it sure saves you getting hand cramps if you don't have to write a multiplication sign (and save on confusion as x is the most common term for an unknown variable) unless you really have to, i.e. between two actual numbers. Quote Link to comment Share on other sites More sharing options...
Le Stu Posted April 12, 2011 Author Report Share Posted April 12, 2011 They're exactly the same thing. You could call it laziness but it sure saves you getting hand cramps if you don't have to write a multiplication sign (and save on confusion as x is the most common term for an unknown variable) unless you really have to, i.e. between two actual numbers.I only substituted x to show that the rules for expanding parenthesis in algebra work. it's no different with the actual numbers. 2 and (9+3) are factors of 24.look at it this way48 / x(9+3)there's no way in hell you'd divide by x first. Quote Link to comment Share on other sites More sharing options...
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