Bosque Posted October 28 Posted October 28 9 and 1 are both possible answers depending on the conventions you use. The other answers are nonsense
Gelato Posted October 28 Posted October 28 Using BIDMAS (or PEMDAS, or BODMAS, they're all the same): 6÷2(1+2) 6÷2(3) The "B" means perform operations inside brackets first, which I've done above. But now there are no more operations to perform inside brackets. It's just the same as 6÷2×3, so we work left to right: 6÷2×3 3×3=9 Interestingly, when I put the expression into my calculator (Casio fx-991EX Classwiz, the most popular scientific calculator used in UK secondary schools until last year when the Casio fx-991CW was introduced), it automatically changes the notation to give: 6÷(2(1+2)) Which is: 6÷(2(3)) 6÷6 = 1 But this is a different problem There are two takeaways for ATRLers: "Brackets first" means giving priority to operations inside brackets Be clear in your notation -Gelato ATRL's resident economist and A* grade A-Level mathematician
AxelFox Posted October 28 Posted October 28 1 hour ago, dumbsparce said: It's 2(1+2) therefore the answer is 9 If it was [2(1+2)] the answer would be 1 Reveal hidden contents I think EXACTLY! 1 hour ago, Cruel Summer said: I voted 1 because people pretending implicit multiplication doesn't exist is annoying It exists, you use square brackets for that. The way the equation is presented does not call for it and there is no 'room for interpretation' whatsoever. The answer is most clearly and definitely 9. 2 1
Cruel Summer Posted October 28 Posted October 28 22 minutes ago, AxelFox said: EXACTLY! It exists, you use square brackets for that. The way the equation is presented does not call for it and there is no 'room for interpretation' whatsoever. The answer is most clearly and definitely 9. From a purely modern textbook perspective, sure, but the reality is that this interpretation conflicts with the natural inclinations of many readers and with the way many people were taught to literally do math. There are old textbooks out there that say to do all multiplication first, and there are more recent examples of sources that say that when presented an equation like this, you perform the implicit multiplication first - no square brackets involved. What if those are the only kinds of sources someone has consumed? We have to acknowledge that representing mathematical problems and equations this way is a matter of language and education, both things that are non-static, and the latter of which doesn't come with equal access to modern standards for all. Problems written this way always generate this kind of divided response, and by not acknowledging the reality that both branches of thought are substantiated by education-backed reasoning, we're doing a disservice to everyone and losing the opportunity to actually teach anyone. The only definitive answer is "don't write equations and problems like this."
ATRL Moderator Bloo Posted October 28 ATRL Moderator Posted October 28 It’s 9. If you got anything else, you’re wrong. 5 1
dumbsparce Posted October 28 Posted October 28 48 minutes ago, Cruel Summer said: From a purely modern textbook perspective, sure, but the reality is that this interpretation conflicts with the natural inclinations of many readers and with the way many people were taught to literally do math. There are old textbooks out there that say to do all multiplication first, and there are more recent examples of sources that say that when presented an equation like this, you perform the implicit multiplication first - no square brackets involved. What if those are the only kinds of sources someone has consumed? We have to acknowledge that representing mathematical problems and equations this way is a matter of language and education, both things that are non-static, and the latter of which doesn't come with equal access to modern standards for all. Problems written this way always generate this kind of divided response, and by not acknowledging the reality that both branches of thought are substantiated by education-backed reasoning, we're doing a disservice to everyone and losing the opportunity to actually teach anyone. The only definitive answer is "don't write equations and problems like this." I don't think anyone on atrl is that old to have been taught from old textbooks. The last time I was taught basic math the Twin Towers still stood proudly and that was almost a quarter of a century ago already
Brooklyn Baby Posted October 28 Posted October 28 The amount of people who voted 9... I have no words 2 3
dumbsparce Posted October 28 Posted October 28 2 minutes ago, Brooklyn Baby said: The amount of people who voted 9... I have no words 2 minutes ago, PrettyHurts said: people not knowing its 9... 4
Cruel Summer Posted October 28 Posted October 28 1 hour ago, dumbsparce said: I don't think anyone on atrl is that old to have been taught from old textbooks. The last time I was taught basic math the Twin Towers still stood proudly and that was almost a quarter of a century ago already It's more about poor areas and underfunded districts IMO. There are textbooks out there from like the 70s that basically had this type of problem "wrong," because at the time it really wasn't as wrong since there's not actually a perfectly consistent standard for this notation that's universally accepted and used - I guarantee there are young adults who were still taught from those books. Maybe even at the time you were in school!
Scandalous Posted October 28 Posted October 28 (edited) it's 9 the Parentheses part of PEMDAS applies to only what's INSIDE the parentheses, once you solve the (1+2) it just turns into multiplication, which you do left to right equally with division but i agree this equation shouldn't even be written this way, it would have a multiplication sign for clarification but hmmm after consulting w some irl friends they get 1 by writing it as a fraction so im confused Edited October 28 by Scandalous
VelvetCrush Posted October 28 Posted October 28 (edited) the way this **** ass problem comes back every few years for discussion... I swear not too long ago this forum had a 20 pages thread about it Edited October 28 by VelvetCrush
dumbsparce Posted October 28 Posted October 28 1 hour ago, Scandalous said: so is there even an actual right answer to this 1
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