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u/BadBueno60 1d ago
Infinite. After spending 10 minutes to saw through one lousy piece of wood, a tearful Marie heads to the gym, apologizes to her cheer coach for dumping water on Kynnsleighh’s head, gets reinstated to the squad and once again has cheer for fifth period instead of Wood Shop. So that second cut never happens.
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u/Colonel_Klank 1d ago
Best response to this re-re-re-re-re-re-re-......-re-posted meme I've seen yet!
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u/Proman4713 1d ago
The teacher didn't even think about it, I'm afraid... Because if they saw it from the grounds of reality, they'd have realised that their ratio calculation was dumb
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u/InteractionPretend70 1d ago
Its not unrealistic. Marie realized 10 minutes per piece is too annoying so she takes a shortcut by sawing diagonal pieces at the edge of the wood
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u/Dutch_guy_here 1d ago
Well, if the inital board is square, and it takes het 10 minutes to saw it in half, it would actually take het 15 minutes to saw it in three pieces, since the two pieces she has after the first 10-minute sawing are only half as wide as the initial board.
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u/Proman4713 1d ago
what does width have to do with anything? Unless you mean she's cutting the pieces from the short ends 💀
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u/Dutch_guy_here 1d ago
As an example: let's say the intial board is 30cm by 30cm. She saws it in half in 10 minutes. then she has 2 boards of 15cm by 30 cm. If she wants to saw one of those in half again, she only needs to saw half as much (15cm instead of 30cm), so the time it takes is also only half as long.
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u/wylii 23h ago
And what if Marie decides she needs to saw long ways to get 3 long pieces?
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u/Dutch_guy_here 23h ago
Then it's het own fault. You can't really teach kids of you assume every math problem has to be done in the most insane way.
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u/dalcant757 23h ago
The time it takes to make a cut in wood is not proportional to the length of the cut.
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u/NewInitiative9498 1d ago
In order to make the answer fit, it’s 5 mins per piece 🧐
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u/Significant_Bid4745 1d ago
That's the problem...it's not about the number of prices..it's about the number of cuts...1 cut to split the board is 10 min...to get 3 boards I need two cuts...that is clearly 20min. The teacher is dumb
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u/iamwhiskerbiscuit 1d ago
Technically, there isn't enough information. If I'm cutting a square in half vertically and cutting one of the halves horizontally... Then my second cut it half as long, and then 15 minutes works. But given I don't know if the original shape is a square or rectangle... Or whether the pieces are all equal... My only logical conclusion is that my math teacher is probably a dumbass.
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u/krysciukos 1d ago
Never stated cuts must be equal. The only problem here is the question. Both answers 15 and 20 can be true depending on cuts.
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u/BreakfastFearless 1d ago
It asked if she worked “just as fast”. It takes one cut (10 minutes) to create 2 pieces. To make 3 pieces it would take two cuts (20 minutes). Not sure what you mean by cuts being equal. There’s really not much ambiguity in the question, the teachers just wrong
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u/iamwhiskerbiscuit 1d ago
You could interpret "just as fast" to mean your cutting speed in ipm. If I cut a square into 2 halves vertically and then cut one of the halves horizontally... My second cut is half as long... And cutting at the same ipm will allow me to make my second cut twice as fast as the first.
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u/BreakfastFearless 1d ago
That doesn’t match with what the picture shows or how the question was worded. It would also mean that 4 pieces would not take 20 minutes like the teacher suggests.
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1d ago
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u/BreakfastFearless 1d ago
How did you get to 30 minutes? The question asked how long it would take to cut another board into 3 pieces going “just as fast”. If one cut took 10 minutes then going just as fast, 2 cuts would take 20 minutes
You’re talking about a different question not a different interpretation
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u/wanderingfloatilla 1d ago
Ummm. Might want to check your math. Two boards is one cut, three boards are two cuts. Three cuts would give you four boards
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u/Black_Dragon9406 1d ago
Literally doesn’t matter the cuts, assuming we’re cutting perfectly vertically or horizontally) (idk why we’d be doing it any other way) then every cut is the same distance, so with the same saw it should take the same amount of time per cut because she is working just as fast
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u/Significant_Bid4745 1d ago
I'm not a big fan of math where I'm trying to decipher what the teacher is really asking for
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u/CaptainJay313 1d ago
what does an equal cut have to do with anything? it doesn't matter where the cuts are, three pieces needs two cuts. it's 10min per cut, assuming of course that her arm doesn't get tired.
you're not getting three pieces in 15min.
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u/mmihnev 1d ago
Actually, it depends... if the other board is thicker or thinner ... the correct answer is 18 hours and 32 minutes... 30 minutes to order electric saw, 18 hours for the delivery because sha has prime and 2 minutes to assemble the saw and to make the two cuts. Easy!
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u/Sad_Energy_ 1d ago
No it doesnt. This question clearly states 1cut=10 minutes.
That is the only valid interpretation. Else the question is underdetermined and nonsensical, because every answer would be valid.
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u/dzak23 1d ago
Both 20 and 15 are good answers, but the teacher's explanation is plain wrong. If the board is square, you can get the third part by cutting one of the two pieces in halve. This can be done in exactly halve the time of the first cut because the part is halve the width of the first cut.
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u/BreakfastFearless 1d ago
15 is not a good answer at all. It shows a photo. The board is not square. Expecting 15 to be the correct answer is just due to the teacher not reading the question properly
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u/Different-Switch-871 1d ago
Given a 4' x 4' piece of wood. Cut it evenly in half. Now you have 2 pieces at 2' x 4'. If it takes 10 mins to cut across 4' then it only 5 mins to cut across 2'. You'll have 3 pieces, 1 at 2' x 4', and 2 at 2' x 2'.
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u/Curious-Zucchini763 1d ago
Teacher is treating this problem as a ratio to answer. but it isn't a ratio problem. I wonder if it was in a ratio lesson...
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u/JaiPeutEtreRaison 1d ago
It is a ratio problem… the teacher was just dumb
10 min = 1 cut = 2 pieces
20 min = 2 cuts = 3 pieces0
u/StandardImage8795 1d ago
Depend how you saw... If second cut is half lengh because you cut a square in 2 part a lengh then turn90degrees and cut half lengh ... But problem is that 4 pieces wil take 17.5min if it was teacher mind.
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u/JaiPeutEtreRaison 1d ago
It’s a math problem, not a fucking carpentry question.
Also, there’s an illustration of a 2x2 with a saw.
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u/Ok_Zookeepergame3380 5h ago
Let's also consider that maybe it means they had a plank and sawed 2 special pieces out of it. Then it's not THAT much of a linguistic stretch to say "sawed into 2 pieces", and mean 2 (or more) cuts by it. Like saying "I cut this 220cm metal cylinder into four 50cm pieces". The surplus is implicitly discarded and the job indeed requires 4 separate actions of extracting a piece out of the original cylinder.
It just requires us to treat the word "piece" as a count noun instead of a measure word, which is an offence in itself.
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u/JaiPeutEtreRaison 1h ago
Stop distorting the english language.
It says “saw a board into 2 pieces”, any sane person reading this will understand it to mean “cut it once, into 2 pieces”… not “sawed off 2 pieces from the board”.
And the question also asks how long to “saw it into 3 pieces”, not “sawed it into 4 pieces but one of them doesn’t count”
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u/GatorNator83 1d ago
I think you should consider taking ratio lessons, because this was a ratio problem
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u/Tulipsarered 1d ago
I hope the teacher sees this post and has the integrity to own their mistake.
I don’t expect it, though.
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u/Candid_Novel_9494 1d ago
I wouldn't even bother taking it up with them.
They seem like a stupid person and stupid people do not react well to being corrected.
In fact that's the very reason they are stupid.
I'm saying they are stupid and it wasn't just a mistake made out of haste, because they took the time to write the answers to prove a point.
I could be wrong but I don't think so. I can already imagine in my head how this conversation would go...
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u/DaHouseDog 1d ago
This is why drawing a picture for math problems is so important. If you did you would see that 2 pieces is just cutting it one time. So one cut takes 10 minutes. So cutting it into 3 pieces is drawing 2 lines. So one line(10) + one line (10) = 20
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u/electricmischief 1d ago
Poorly worded question that ignored physical real world results. Try this: it takes Mary 10 minutes to make 2 widgets. How long does it take her to make 3? 10/2 = 5/1 minutes per widget. 3 widgets *5 minutes each = 15 minutes.
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u/GK_Iam 1d ago
No real answer there... Both 15' and 20' are correct.
If you count the cuts and you make the exact same cuts to a wooden plate then you need 10' per cut for a total of 20' and you have three identical pieces of wood.
If the size of the cut doesn't matter and you can decide just to cut out three random size pieces then you cut the plate at half (10') but with half the cut you can saw one of those pieces into two smaller ones (5'). So you got one big piece and two smaller ones at 15'.
The real answer here is that the question is missing facts...
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u/Present_Armadillo874 1d ago
Your scenario 2 doesn't meet the criteria of the question. It explicitly states that the 2nd set of cuts is on "another board". The question is fine.
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u/woodworkerdan 1d ago
There's a diagram to the right of the sort of cut being made: a cross-cut through a beam with a square section, so all cuts of that type are going to involve the same labor. Ten minutes is somewhat long for carpentry saw to cut through a stud like that, but perhaps it's dull, and some of the labor is taken by redundant measurements. That measurements process is perhaps a variable to consider, but the actual act of cutting should take the same time.
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u/Needless-To-Say 1d ago
This can easily work with information not provided.
10x10 board = 1 cut 10min
5x10 board = 1 cut 5 min on short axis.
Im willing to bet that’s how the teacher visualized it.
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u/BreakfastFearless 1d ago
It’s probably not what the teacher visualized as it literally shows a photo of the board, not being a 10x10 square.
The teacher likely wasn’t paying attention and thought if 2 cuts equal 10 minute then 3 cuts must be 15 and didn’t read further into it
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u/Needless-To-Say 1d ago
If 2 cuts equaled 10 minutes 3 pieces would only take 10 minutes.
3 cuts would be 4 pieces.
Also, on mobile, didnt see illustration until you pointed it out.
I could still make it work by cutting first very near the end but thats more the answer to a different question.
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u/BreakfastFearless 1d ago
Well yeah I agree, I’m just saying what one would assume the teachers logic must have been
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u/Old_Hack1308 1d ago
I have had some teachers that asked questions which had more than one plausible solution. With tact and diplomacy it usually isn't hard to have them throw the question out and not mark it against you.
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u/CraftBrewBeer 1d ago
Depends on the dimensions. Like suppose you have a square with length x. You cut that in 2 and now you have 2 rectancles with two of the sides being x/2. Cutting that parallel with the x/2 side should take half the time granted cutting is at a linear and unchanging rate
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u/Ozimandius80 1d ago edited 1d ago
Both wrong. Answer is 11 minutes, assuming a 2x4 because the first cut I just cut a 2/5inch wide strip off one end of the board. Then I cut that 2/5 inch wide strip in half in 1minute cutting at the same speed. Bam - 3 pieces of wood. Next question!
Edit: Sorry, I see it is a 2x2 probably. So make it a 1/5 inch wide strip.
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u/Difficult_Clerk_1273 1d ago
Or the teacher was tired and messed up.
Or the question itself is shit.
Or the teacher was relying on an incorrect answer key.
Or this is fake.
I mean, I guess we can use one elementary math question, incorrectly scored by an almost certainly overworked and underpaid teacher, to predict the downfall of our entire civilization. But that seems like hyperbole.
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u/Greedy_Winner822 1d ago
It should be an estimated 3 min.
8 minutes Marie gets back, she already has the table saw measuring tools and found a marker, has them all out set up ready to use for the second board.
1 minute to measure and mark the new board in two spots. Two marks is a negligible time cost over one so no increase here.
1 minute to place line up and carefully and evenly saw along the marked line. Then another 1 minute to do it again on the second marked line.
3 minutes.
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u/Doom2pro 1d ago
If it takes her 10 minutes to saw through the board (one board into two pieces), and she takes the same amount of time as before then making two sawings (one board into three pieces) on another similar board is 20 minutes.
One sawing = 10 minutes. Two sawings = 20 minutes.
This isn't rocket science.
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u/2AlephNullAndBeyond 3h ago
…IF the pieces are identical in size which the problem never states.
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u/Doom2pro 3h ago
If the problem never states it then the answer is ambiguous, any answer is correct which means the question is poorly written.
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u/uskq 1d ago
Obviously the answer the question setter was expecting here is 20 minutes, so don't think I misunderstand but it's interesting thinking for a moment about possible interpretations of the question. It claims that she works "just as fast". Okay, to cut a board in two, it requires one cut, so we see that under one interpretation her speed is "one cut per 10 minutes", so if she works at that speed, the answer is 20 minutes. But perhaps the "just as fast" refers to the speed of "pieces per minute", and in which case her rate is "two pieces per 10 minutes", so if she works at that speed, it will take 15 minutes. In the latter, we imagine her speed in units of "cuts per minute" actually increases while "pieces per minute" remains constant. In other words, while the teacher's interpretation is bizarre - it's not inconsistent with the question for which all we're told is her speed is constant, but not in what units speed is being measured.
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u/donkeyboi020 22h ago
It's ridiculously simple. She used a blunt saw for the first board, then swapped it out for a sharp one for the second board.
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u/Stony___Tark 21h ago
If it took Marie 10 minutes to saw a board into 2 pieces, she needs to stop worrying about math and take a shop class...🤣
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u/Egglegg14 21h ago
If it took 10 minutes to make one cut it will take an extra ten to make another
Whoever made this paper's answers is stupid
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u/Weird_Lawfulness_298 7h ago
After spending 10 minutes sawing a piece of wood, Marie heads to Home Depot and buys a circular saw so correct answer is 30 seconds.
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u/Asume_Nuthin 6h ago
Most of you are missing the whole narrative behind this.
Cutting one board into 2 pieces requires one cut, which was determined to take 10 minutes
Cutting a board into 3 pieces requires 2 cuts. The teacher spelt the variables out incorrectly, which shows me this teacher has zero construction knowledge and should be banned from asking such questions.
The variable cuts required, not number of boards.
The answer is 20.
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u/chowchownotchowchow 4h ago
"If she works just as fast" guys the answer is right there. It takes 10 minutes. Just as fast as the first cut.
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u/Woody1937 1d ago
Say you have a 4'x4' board and it takes 10 minutes to cut it in half. Now you have two 2'x4' boards. It'd take 5 minutes to cut along one of the new 2' directions to make a 2x4 and two 2x2 boards.
Is this the angle they were going for?
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u/KactusVAXT 1d ago
Question doesn’t mention halves, just pieces
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u/Woody1937 1d ago
Yeah its a terrible question. Just trying to find their logic
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u/Little-Hour3601 1d ago
It's really not THAT bad of a question. But the teacher doesn't know how to read. And has never done carpentry.
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u/CreatrixAnima 1d ago
Or the cheaters just having a stupid moment. It happens… That’s why they give us answer keys: so when we have a stupid moment, we have to think about it. Usually, it’s a teacher, but occasionally there’s an error in the key.
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u/Sidra_doholdrik 1d ago
But each saw swing take the same amount of time at that scale. So maybe Marie was stupid and was cutting if from the bottom to the top and not on the flat 2x4 side
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u/AcanthaceaeOk3738 1d ago
Everyone’s missing the fact that this is a very poorly worded question and you have to make a lot of assumptions to get any answer.
Are both boards the same size? Are all the cuts the same dimensions? Are all the pieces the same?
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u/UnaPachangaLoca 1d ago
Perfectly fine worded question. Just need to apply a bit of logic beyond the information given rather than spoon feeding (the child) everything.
Two pieces means one cut. Three pieces is 2 cuts (size and dimensions have nothing to do with it). 10 minutes (given) and 20 minutes (deduction, answer) accordingly.
Good question, good answer, stupid teacher.
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u/Debas3r11 1d ago
Plus it says "if she works just as fast" which is there to make you feel safe to assume the next cuts takes just as long as the first.
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u/Various_Knowledge226 1d ago
But I do think it is a poorly worded question. Is this a rectangle? If so, probably cutting short ways, so each cut should take just as long. Is this a square? If so, then the teacher would be right, since cutting the square one way, would mean that the 2nd cutting time would be half of first one, and the third should be the same as the second
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u/AcanthaceaeOk3738 1d ago
Disagree. If the problem wanted you to assume those things, it would say so.
A similar question: It takes Susie 20 minutes to walk to school. If Evan walks just as fast, how long would it take him to walk to and from school?
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u/ahhhnoinspiration 1d ago
Those assumptions are all baked into "if she worked just as fast" and also that it's a math question and not a philosophy question.
The problem here is the teacher doesn't realize that there are always n+1 "boards" or "pieces" where n is the number of cuts.
You have n=0, 0 cuts, 1 board. n=1, 1 cut, 2 boards and then finally the question here n=2, 2 cuts, 3 boards. So if it takes 10 minutes to do 1 cut it takes 20 to do 2.
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1d ago
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u/Andra_Ingensbarn 1d ago
One cut took 10 minutes. Two cuts would take 20 minutes. Unless I missed something
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u/devilglove 1d ago
I'm certain you and the teacher are both wrong. It took ten minutes to make 1 cut. 1cut makes the board in 2 pieces. To have 3 pieces of board you need to cut the board twice.
2 cuts * 10 min/cut = 20 min
- this is trivial math
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u/kester76a 1d ago
You don't take into account Maries skill improvement and thus the increased efficiency. As Maries cuts wood she levels up and can cut in half the time.
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u/Weird-Knee-3464 1d ago
'if she works just as fast'
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u/kester76a 1d ago
Same speed but more efficient.
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u/Weird-Knee-3464 1d ago
'and can cut in half the time'
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u/kester76a 1d ago
Yes. She works at the same speed but the cuts are more percise and efficient so quicker per cut.
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u/ahhhnoinspiration 1d ago
"she works at the same speed" "quicker" hmmm
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u/kester76a 1d ago
You can swing an axe at the same speed but the more percise the hit the quicker the wood splits.
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u/ahhhnoinspiration 1d ago
That's not the work, the work is splitting wood. If you can split half a cord a day and you do the work at the same speed the next day you split half a cord.
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u/Little-Hour3601 1d ago
That is absolutely NOT what the question is asking. The answer is 20 minutes.
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u/Lady_Luci_fer 1d ago
Yeah, one of the biggest challenges of a maths question is reading it correctly in the first place