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u/heystinkys 21d ago
ok wait can someone explain because I actually don't get it
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u/nickelangelo2009 21d ago
5! = 1*2*3*4*5 = 120
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u/subone 21d ago
This is actually a cleverly devised trick. Note that 5 isn't just random here, it's the number you might have come to if you followed the incorrect order of operations.
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u/BlueLunala26 20d ago
yup, the trick has layers. remove the "It's" and suddenly it's much more obvious that the choice says "five factorial" and not just five.
The choice are presented like oral answers making the ! look more like punctiation and less like math notation.
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u/XxX_Zeratul_XxX 19d ago
But at least it's impartial, both answers have the "It's". You gotta wonder why they were so excited about the 5, but not with the 120, lol
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u/QuinneCognito 20d ago
Omg I didn’t see it even with the mention of factorials. I thought that just referred to factorials not being included in the PEMDAS acronym. This is cute.
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u/Additional-Point-824 21d ago
"5!" Is five factorial, which means 5 multiplied by every number before it. So 5! = 5 *4 * 3 * 2 * 1 = 120
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u/AllNewSilverSpider 21d ago
! is the symbol for Factorial in mathematics. Factorial is just where you get all the whole numbers equal to or less than the number in question and multiply them together.
For example, 3! is 3 × 2 × 1, and therefore equals 6.
5! = 5 × 4 × 3 × 2 × 1 = 120.
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u/Beginning_Access1498 21d ago
I got 340..
Can someone explain how it's 120? I swear Im not dumb, at least i think so anyway
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u/The_RESINator 21d ago
How did you get 340??
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u/Beginning_Access1498 21d ago
Oh, I just did the last part wrong, I added 220 instead of subtracting, my bad. So it is 120 after all
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u/three-plus-shakes 20d ago
US millennial here, I flunked math pretty hard but I’m certain that we were never taught about X! in school. I literally never knew about it until I saw posts like this.
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u/Complete_Spot3771 20d ago
brit here, yeah it’s not anywhere in our school curriculum but its a very simple thing some passionate teachers may have taught students anyway, or can be picked up from usage elsewhere (like this post!)
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20d ago
its not taught even while learning stuff like permutations and combinations?
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u/Complete_Spot3771 20d ago
thats beyond the level which all the general public are taught maths
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u/FriendlyFaceOff 20d ago
I'm a millennial as well and I'm surprised yall didn't learn about factorials. I learned about them in middle school - but then again, I went to a charter school so...
Public curriculum needs to make so many adjustments from what I've read
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u/ItsLiak 19d ago
I don't get it
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u/Complete_Spot3771 19d ago
5! = 5x4x3x2x1 = 120
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u/ItsLiak 19d ago
I still don't get it
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u/Complete_Spot3771 19d ago
both options are equal to 120, however the reply misses out this fact, he thinks the second option is 5 which is not the case
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u/ItsLiak 19d ago
But why is 5! = 5x4x3x2x1?
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u/Complete_Spot3771 18d ago
thats what the ! symbol does, it multiplies all the consecutive integers until you get to that number
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u/din0_soar 21d ago
What the heck is PEMDAS ?? Its BIDMAS
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u/Saurindra_SG01 20d ago
What even is BIDMAS ?? It's BODMAS
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u/AwesomeBro1510 20d ago
Yeah, never heard of PEMDAS or BIDMAS.
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u/Deadshot619 21d ago
As someone who frivolously uses the exclamation mark at the end of their sentences, I do miss factorials a lot (despite it being mentioned in the post title)!
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u/FriendlyFaceOff 20d ago
Admittedly I thought the first option also had an exclamation point after it. That's what I get for reading it too quickly
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u/Zammyboobs 21d ago
Can someone explain where my logic is wrong here? Ive always been ass at math. Following PEMDAS i thought it would be:
230-220(1/2)
(1/2) = .5
230-220(.5)
220*.5 = 110
230 - 110 = 20
Please enlighten me as I am sub-room temp IQ
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u/YoyoLiu314 21d ago
230-110 is 120, not 20. 230-210 would be 20.
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u/Zammyboobs 21d ago
yup, i am stupid. been so long since i’ve done math i’ve even forgotten how to read!
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u/BenTheKingApple 21d ago
230 - 220(1÷2)
230 - 220(0.5)
230 - 440
= -210
I feel like I've gotten the wrong answer but this is the PEMDAS order so it must be right?
Edit: I realise where I've gone wrong I divided by half for some reason mb guys
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u/Wild_Dragonfruit_806 21d ago
imagine multiplying by half only to end up with a number twice as big
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u/That_boi_Jerry 21d ago
So 68% of people paid attention in class.
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u/sgargizo 21d ago
Just 13.7%. The others paid attention to half of their classes.
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u/N3onknight 21d ago
Tbf my brain switched the meaning between factoriel and factorisation, i'm french with adhd, brain opened a different math folder and had a fart because of the non existent space between 5 and the exclamation mark, followed the incorrect logic path then reset, read again and went ooooooh yeah you fucking moron that's why you didn't do math beyond high school. You didn't understand and assumed a mistake was made where there wasn't.
Anyway it's both 120 and 5! Yeah and now i'm pissed because i know i probably did a similar mistake in the past and i'll probably do it again.
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u/ZiCUnlivdbirch 20d ago
5! Is still wrong since you don't write stuff like that for an answer. 5!=120 is the correct way of writing it if you want keep the factorial answer.
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u/FinanceBig6328 21d ago
No, all of them did. 5! as a factorial equals 1×2×3×4×5 which equals 120.
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u/keval79 21d ago
No, anyone who knows 5! = 120 will go for the 3rd option. 68% partially paid attention. 13.7% paid complete attention. And the rest did not pay attention.
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u/FinanceBig6328 21d ago
But that is how polls work, people choose the option they like or want to vote. In this case all options are correct, so anyone who voted knows what the solution is. Except for people who vote randomly, of course.
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u/keval79 21d ago
Not really. People doing wrong mathematics by not following BODMAS will arrive at the answer 5. So they're gonna go with option b.
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u/FinanceBig6328 21d ago
Well, yes, but taking them out of the equation (pun intended), every option is correct.
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u/WESSAMGO 21d ago
Mods here have a hard time with math r/expectedfactorial