|
View Poll Results: 48÷2(9+3) = ??? | |||
2 | 29 | 42.03% | |
288 | 37 | 53.62% | |
Trout | 3 | 4.35% | |
Voters: 69. You may not vote on this poll |
|
Thread Tools |
04-27-2011, 11:02 PM | #1 | ||
College Benchwarmer
Join Date: Jun 2008
Location: JBLM, WA
|
Simple Math?
Many have probably seen this in the past few weeks as it has been quite popular on the internet, but I have not seen a thread on this here and am curious what this board thinks.
48÷2(9+3) = ???
__________________
I killed a wolf and I liked it. Last edited by Commo_Soldier : 04-27-2011 at 11:08 PM. Reason: Add Images |
||
04-27-2011, 11:05 PM | #2 |
Bounty Hunter
Join Date: Oct 2000
Location: Pittsburgh, PA
|
Seems pretty obvious to me.
__________________
No, I am not Batman, and I will not repair your food processor. |
04-27-2011, 11:06 PM | #3 |
College Benchwarmer
Join Date: Jun 2008
Location: JBLM, WA
|
My understanding is the 2 should not be done with the bracket as you solve what is in the bracket first. Once you add the 9 and 3 together the bracket can disappear and a multiplication sign now exists. Then following the order of operations you get 288.
__________________
I killed a wolf and I liked it. |
04-27-2011, 11:07 PM | #4 | ||
Favored Bitch #2
Join Date: Nov 2007
Location: Here
|
Pie?
__________________
Quote:
Quote:
|
||
04-27-2011, 11:08 PM | #5 |
Bounty Hunter
Join Date: Oct 2000
Location: Pittsburgh, PA
|
Yeah, that's what I would think. Just because there's no multiplication sign visible doesn't mean that you evaluate the 2*12 before you divide 48 by it.
__________________
No, I am not Batman, and I will not repair your food processor. |
04-27-2011, 11:09 PM | #6 |
Bounty Hunter
Join Date: Oct 2000
Location: Pittsburgh, PA
|
Now I see the images, and I guess both Texas Instruments and Casio have some 'splaining to do.
__________________
No, I am not Batman, and I will not repair your food processor. |
04-27-2011, 11:10 PM | #7 |
College Benchwarmer
Join Date: Jun 2008
Location: JBLM, WA
|
That is what I'd think, but I've seen threads on other boards that are almost 3000 posts on such a seemingly obvious problem.
__________________
I killed a wolf and I liked it. |
04-27-2011, 11:11 PM | #8 |
College Starter
Join Date: Nov 2003
Location: CT via PA via CA via PA
|
FOFC is behind the times. This has been breaking the internet for the last month. ; )
|
04-27-2011, 11:12 PM | #9 | |||
Favored Bitch #2
Join Date: Nov 2007
Location: Here
|
Quote:
See, I would think that the parentheses remain, even after you add the 9+3, so you would multiply first, then divide by 48. My calculator's answer is 2 (which is the same as when I did it in my head). *shurg*
__________________
Quote:
Quote:
|
|||
04-27-2011, 11:19 PM | #10 |
College Starter
Join Date: Jun 2003
Location: Federal Way, WA
|
I always took 2(9+3) to basically represent one number on that level of the problem, a number that needed to be addressed and placed before you work out anything else on the same level of the problem.
|
04-27-2011, 11:21 PM | #11 | |
Bounty Hunter
Join Date: Oct 2000
Location: Pittsburgh, PA
|
Quote:
48/2(9+3)... 48/2(12)... 48/2*12... 24*12... 288 Although from what folks are saying here, there's some faction on the internet and some calculators that disagree.
__________________
No, I am not Batman, and I will not repair your food processor. |
|
04-27-2011, 11:21 PM | #12 |
Bounty Hunter
Join Date: Oct 2000
Location: Pittsburgh, PA
|
Dola
To get the number to be 2, I would think it'd have to be written as 48/(2(9+3)).
__________________
No, I am not Batman, and I will not repair your food processor. |
04-27-2011, 11:23 PM | #13 |
Grizzled Veteran
Join Date: Nov 2006
Location: Backwoods, SC
|
4th grade.
Please Excuse My Dear Aunt Sally Parenthesis, Exponents, Multiply, Divide, Add, Subtract 48 /2(9+3) Parenthesis, check 48/2(12) Exponents, nope Multiply, check 48/ 24 Divide, check 2 done. |
04-27-2011, 11:26 PM | #14 | |
Bounty Hunter
Join Date: Oct 2000
Location: Pittsburgh, PA
|
Quote:
5-4+3 == 4 5-4+3 != -2
__________________
No, I am not Batman, and I will not repair your food processor. |
|
04-27-2011, 11:39 PM | #15 |
Grizzled Veteran
Join Date: Nov 2006
Location: Minnesota
|
|
04-27-2011, 11:42 PM | #16 | |
General Manager
Join Date: Oct 2000
Location: The Satellite of Love
|
Quote:
That's the issue with this. There is no standardized order of operations when it comes to "bracket multiplication". Some people say it makes it go ahead of normal division and multiplication in the order of operations (Otherwise it would be written as 48 ÷ 2 * (9+3) ), others say it's just short hand for normal multiplication. But there's no formal rule about it. |
|
04-27-2011, 11:44 PM | #17 |
Grizzled Veteran
Join Date: Nov 2006
Location: Minnesota
|
|
04-27-2011, 11:48 PM | #18 | |
Bounty Hunter
Join Date: Oct 2000
Location: Pittsburgh, PA
|
Quote:
To sabotai's point, if there's no formal rule for the "bracket multiplication", then we'll never get everybody to come to agreement. The points both sides make are pretty obvious. It's just a matter of which you agree with. Given that this makes the discussion rather futile, I guess I'm done here.
__________________
No, I am not Batman, and I will not repair your food processor. |
|
04-27-2011, 11:50 PM | #19 |
General Manager
Join Date: Oct 2000
Location: The Satellite of Love
|
That's a separate problem. Written that way, you'd do the multiplication first regardless of the debate over the way the multiplication is written since you always fully work out the numerator and denominator first before dividing.
48 ÷ 2(9+3) is not the same thing as that. For instance: 40 * 2 / 10 * 10 If that division sign is shorthand for a fraction, then the answer is 0.8, since you do both multiplications first. If it's simply division, than the answer is 80, since you work left to right. |
04-27-2011, 11:51 PM | #20 |
Coordinator
Join Date: Apr 2001
Location: Early, TX
|
Math sucks.
__________________
Just beat the devil out of it!!! - Bob Ross |
04-27-2011, 11:55 PM | #21 |
Grizzled Veteran
Join Date: Nov 2006
Location: Minnesota
|
Well shit. I have we even come to a time when we cant even agree on math answers.
I always assumed the order was like CU Tigers post but now the more I am reading up on this it appears around 50 percent of the nation use the same method as I believe Pumpy is using where P E MD AS |
04-27-2011, 11:56 PM | #22 | |
General Manager
Join Date: Oct 2000
Location: The Satellite of Love
|
Quote:
Yes, it's just like every other debate on the internet. It's just what I read when it looked it up a week or two ago. There may be a formal ruling somewhere, but Google is keeping it secret from me. |
|
04-27-2011, 11:58 PM | #23 | ||
College Benchwarmer
Join Date: Jun 2008
Location: JBLM, WA
|
Quote:
There are actually two ways for it to be written. So I believe it is safer to stick with the order of operations rather than pick which way it should be written out on paper. Quote:
I'd argue if there is no formal rule one should go with a formal rule. Order of operations states you complete what is only inside the parentheses first. When the 2 appears next to them all it really is saying is multiply in shorthand as you stated. Which to me means it should be treated as such in the order of operations.
__________________
I killed a wolf and I liked it. |
||
04-28-2011, 12:00 AM | #24 | |
College Benchwarmer
Join Date: Jun 2008
Location: JBLM, WA
|
Quote:
If we are going off of Google...
__________________
I killed a wolf and I liked it. |
|
04-28-2011, 12:01 AM | #25 |
College Benchwarmer
Join Date: Apr 2008
Location: Sterling Heights, Mi
|
I believe the answer is 288
48/2*(9+3) = ??? 48/2*12= 24*12= 288 |
04-28-2011, 12:07 AM | #26 | |
General Manager
Join Date: Oct 2000
Location: The Satellite of Love
|
Quote:
There's also the rule that a(b + c) = (ab + ac) So that 48 ÷ 2(9 + 3) = 48 ÷ ((2 * 9) + (2 * 3)) = 48 ÷ (18 + 6) = 48 ÷ 24 = 2 |
|
04-28-2011, 12:13 AM | #27 |
Grizzled Veteran
Join Date: Nov 2006
Location: Minnesota
|
|
04-28-2011, 12:21 AM | #28 |
Hall Of Famer
Join Date: Dec 2003
Location: the yo'
|
You guys probably stand up to wipe your asses after you take a shit too, i bet. 288?gtfo---->
|
04-28-2011, 12:41 AM | #29 |
General Manager
Join Date: Oct 2000
Location: The Satellite of Love
|
There's a very easy way to find out which is the correct answer, though. Replace one of the values with "x" and try to solve for both answers. I'll replace the 2 outside of the brackets with an x and which ever answer solves "x = 2" (to get us back to the original equation) is the correct answer.
48 ÷ x(9+3) = 288 48 ÷ (9x + 3x) = 288 48 ÷ 12x = 288 48 ÷ 12x * 12x = 288 * 12x (The two 12x on the left cancel each other out) 48 = 288 * 12x (divide both sides by 288) 48 ÷ 288 = 288 * 12x ÷ 288 (the two 288s on the right cancel out) 48 ÷ 288 = 12x (now divide both sides by 12) 48 ÷ 288 ÷ 12 = 12x ÷ 12 48 ÷ 288 ÷ 12 = x 0.013888888888888888888888888888889 = x Well that didn't work out. Let's try 2 48 ÷ x(9 + 3) = 2 48 ÷ (9x + 3x) = 2 48 ÷ 12x = 2 48 ÷ 12x * 12x = 2 * 12x (The two 12x on the left cancel each other out) 48 = 2 * 12x (divide both sides by 2) 48 ÷ 2 = 2 * 12x ÷ 2 (the two 2s on the right cancel out) 48 ÷ 2 = 12x (now divide both sides by 12) 48 ÷ 2 ÷ 12 = 12x ÷ 12 48 ÷ 2 ÷ 12 = x 2 = x The answer is 2. |
04-28-2011, 12:50 AM | #30 | |
Bounty Hunter
Join Date: Oct 2000
Location: Pittsburgh, PA
|
Quote:
You're taking a hell of a leap here on the bolded parts. The distributive property doesn't tell you to put those pieces in parentheses. a(b + c) = ab + ac, necessarily. a(b + c) does not imply (ab + ac) when put into an equation as above.
__________________
No, I am not Batman, and I will not repair your food processor. |
|
04-28-2011, 12:54 AM | #31 | |
General Manager
Join Date: Oct 2000
Location: The Satellite of Love
|
Quote:
Yes, yes, I know the debate is if you can do that or not. I'm just being difficult. And bored. And wide awake at 2 am. I'm just happy I got Serious Pumpy to make a special appearance on FOFC. |
|
04-28-2011, 01:01 AM | #32 |
Coordinator
Join Date: Oct 2000
Location: Concord, MA/UMass
|
2/3
|
04-28-2011, 01:01 AM | #33 | |
Bounty Hunter
Join Date: Oct 2000
Location: Pittsburgh, PA
|
Quote:
I'll acknowledge that a case could be made either way, so I'll concede this as somewhat ambiguous. With that said, I still can't parse the logic that shows the answer as 2, but that could be my fault. And I'm only serious because I used up all my fun at bowling a few hours ago. So you did catch me at the right time.
__________________
No, I am not Batman, and I will not repair your food processor. |
|
04-28-2011, 01:12 AM | #34 |
Coordinator
Join Date: Dec 2003
Location: Sydney, Australia
|
I haven't heard of this till just now, but using what I was taught in high school, I got 288.
__________________
Politics, n. Strife of interests masquerading as a contest of principles. --Ambrose Bierce |
04-28-2011, 01:13 AM | #35 |
Hall Of Famer
Join Date: Dec 2003
Location: the yo'
|
|
04-28-2011, 01:29 AM | #36 |
Pro Starter
Join Date: Jan 2011
Location: Madison, WI
|
...I'm just confusing myself.
Last edited by britrock88 : 04-28-2011 at 01:33 AM. |
04-28-2011, 01:38 AM | #37 |
Grizzled Veteran
Join Date: Nov 2006
Location: Minnesota
|
48÷2(9+3) = ???
That part screws me up ÷ 48/2(9+3)=288 Either learned or assumed the fact that the 2 was linked to the parentheses made me think I needed to multiply that part first. In order for this equation to equal 2 it should look like 48/(2(9+3)) Id like to change my vote Last edited by jbergey22 : 04-28-2011 at 01:41 AM. |
04-28-2011, 01:47 AM | #38 |
lolzcat
Join Date: Oct 2000
Location: Annapolis, Md
|
The answer I get is too gross to share.
|
04-28-2011, 01:57 AM | #39 | |
Grizzled Veteran
Join Date: Oct 2000
Location: Wisconsin
|
Quote:
That is the method I was taught so I got 288.
__________________
You, you will regret what you have done this day. I will make you regret ever being born. Your going to wish you never left your mothers womb, where it was warm and safe... and wet. i am going to show you pain you never knew existed, you are going to see a whole new spectrum of pain, like a Rainboooow. But! This rainbow is not just like any other rainbow, its... |
|
04-28-2011, 02:15 AM | #41 |
College Benchwarmer
Join Date: Apr 2003
Location: Lexington, KY
|
Anyone that says 2 is wrong. There is no ambiguity. If you want to use the distributive property, then 24 (not 2) must be distributed over the additive clause so it becomes (9*24) + (3*24).
Last edited by TargetPractice6 : 04-28-2011 at 02:17 AM. |
04-28-2011, 02:18 AM | #42 |
n00b
Join Date: Jan 2001
Location: Naperville, Il USA
|
obviously the correct answer is simply 42
|
04-28-2011, 02:22 AM | #43 |
Coordinator
Join Date: Oct 2000
|
|
04-28-2011, 05:22 AM | #44 |
College Starter
Join Date: Dec 2006
|
It's been a while since I've contemplated this type of ruleset with any conscious effort.
Going on what I recall being taught (which may not be the correct recollection)...my answer would have been 2. After checking with Excel, I see I am incorrect (btw...excel forces the * between the 2 and the (9+3) ). But thinking about it further...I see I would be wrong on many occasions. 5+3/1+3 = 11 11 doesn't feel natural to me as I would tend to solve the sides of the fraction (in my mind) and come up with 2. Hmm...not much of a point to my post other than to point out how evil & tricky the number 2 can be. Last edited by SteveMax58 : 04-28-2011 at 05:23 AM. |
04-28-2011, 05:28 AM | #45 |
College Prospect
Join Date: Jul 2001
Location: Newcastle, Australia
|
I saw this problem on another site. I teach Math and have a Math degree and it is funny to me that all of the mathematicians agree that the answer is 288.
|
04-28-2011, 06:30 AM | #46 |
Pro Rookie
Join Date: Jun 2012
Location: Bahston Mass
|
__________________
There's no I in Teamocil, at least not where you'd think |
04-28-2011, 07:10 AM | #47 |
Coordinator
Join Date: Oct 2000
Location: Big Ten Country
|
Well, it's a good bit of comeuppance for anyone who's ever said, "why do we need to learn this stuff? Let the calculator do it."
|
04-28-2011, 07:20 AM | #48 | |
Pro Starter
Join Date: Jan 2002
Location: Pittsburgh
|
Quote:
This is the most incomprehensible part of this whole thread.
__________________
"Do you guys play fast tempos with odd time signatures?" "Yeah" "Cool!!" |
|
04-28-2011, 07:54 AM | #49 |
College Benchwarmer
Join Date: Nov 2003
|
288 looks right to me. Evaluate the parenthesis first, then work left to right since division and multiplication are both the same level of "importance".
|
04-28-2011, 07:56 AM | #50 |
Pro Starter
Join Date: Oct 2000
Location: Cary, NC
|
This is why when I write code, I put all the parentheses in to make sure the compiler evaluates it in the order I intended. I'd hate for the PS3 compiler to evaluate it one way and the 360 compiler to evaluate it another.
I agree, the original formula is a stupid way of writing out what you want, just like 4 * 2 / 10 * 3 is stupid. Put the parentheses in to be clear. That said, I'm on the side of "you solve math problems via simplification". So when you write 48 / 2 ( 9 + 3 ) you get: 48 / 2 (12) = 48 / 2 * 12 = 24 * 12 = 288 Anyone else is just getting tricky with the formula. They're not WRONG per se, they're just going about math the hard way...
__________________
-- Greg -- Author of various FOF utilities |
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
Thread Tools | |
|
|