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Clearly worded?
Yes. It's fine as it is.  5%  [ 1 ]
Yes, it's clear, but you should still reword it.  11%  [ 2 ]
No, it's amgibuous.  82%  [ 14 ]
It's clearly worded, but you're wrong.  0%  [ 0 ]
Total Votes : 17

Author Message
dethwing
DeTheeThaw

 Posted: Tue Jan 17, 2012 8:48 pm    Post subject: 1 Had a problem on a HW like this: Solve the problem. A course meets 5 times a week. One student misses class 2 days apart. A second student misses class 7 days apart. They were both absent on the second day of class. What is the next class day when both will be absent again? My class and I apparently disagree on the meaning of "2 days apart". I said it meant 2 days later, so if you miss Monday, you miss Wednesday. They [Or at least, some of them] argued that it meant there were 2 days in between. So if you Monday, you miss Thursday. What do you folks say? Is the problem worded clearly? Are my students crazy?
Trojan Horse
Daedalian Member

 Posted: Tue Jan 17, 2012 9:03 pm    Post subject: 2 It's ambiguous. There are other ambiguities too: 1. You said the course meets 5 days a week. Which 5 days? (Don't laugh. Some colleges have courses on Saturdays.) 2. Even assuming that it is Monday through Friday, what happens on weekends? Let's pick an interpretation of what the first student does; let's say there are two days in between each missed class. What happens if that student misses class on Friday. When does he next miss class? Monday (with two days in between)? Wednesday (with two classes in between)? What if he misses class on Thursday; then when will his next miss be? Too many ambiguities. Throw the question out.
dethwing
DeTheeThaw

 Posted: Tue Jan 17, 2012 9:09 pm    Post subject: 3 It was intended to mean class days. So if you miss Friday, you miss Tuesday. But I can see that being a problem.
MatthewV
Daedalian Member :_

 Posted: Tue Jan 17, 2012 9:40 pm    Post subject: 4 Two days apart-- I would say it means missing Monday, being present for two days, and then missing another day. If I was to see this on a test, I would clearly state my position and then solve with my assumptions. I would do this because I find the wording to be ambiguous.
extropalopakettle
No offense, but....

Posted: Tue Jan 17, 2012 11:13 pm    Post subject: 5

 dethwing wrote: It was intended to mean class days. So if you miss Friday, you miss Tuesday. But I can see that being a problem.

Then the "5 days a week" is completely irrelevant, no?

One misses every 2nd day, the other every 7th. Their absences coincided on the 2nd day. When will they next coincide again? (answer: on the 14th class day after the 2nd class day, ie. the 16th class day (14 being the LCM of 2 & 7))
Zag
Tired of his old title

 Posted: Wed Jan 18, 2012 2:35 am    Post subject: 6 In any case, "2 days apart" doesn't suggest repeating, like "every 2nd class" does. If you said, "the two times he missed class were only 2 days apart," then I don't think anyone would be confused. It's when you try to assume that it's a repeating thing that it starts to become awkward.
Jedo the Jedi
Paragon in Training

 Posted: Wed Jan 18, 2012 3:18 am    Post subject: 7 I thought it was a repeating thing, hence the nature of the question. "If these two students constantly miss at these intervals, at what point will their absences converge?" I'm with extro, and I think the logic to answer the question doesn't require the clarity. Tell your whiny students they all fail._________________Paragon Tally: 18 mafia, 3 SKs (1 twice), 1 cultist, numerous chat scum...and counting.
Neo
Daedalian Member

 Posted: Wed Jan 18, 2012 4:06 am    Post subject: 8 My first reading was your intended definition Dethy, but I did wonder how it would apply to a Friday. The girlfriend interpreted it as some of your students did, and also asked about Friday. FWIW, our backgrounds are similar. Physics with math minors, and some time working in education after. Had we been classmates and discussing the problem, it would have led us to asking you for clarification. Though it was fairly straightforward to solve, so the likelihood that we talked about it would be low, thus would have turned it in under differing interpretations. We both feel it's linguistically ambiguous. It happens. I would see no problem with awarding full points to anybody who read it the other way and solved it correctly. They're still showing mastery of the issue at hand, which was how to approach and solve the problem. It would be wrong to punish them for the other interpretation._________________ Ad Astra
dethwing
DeTheeThaw

 Posted: Wed Jan 18, 2012 4:16 am    Post subject: 9 The funny thing is, it's not my wording. I took the class from someone else who has been using this wording for ages. I read it, knew instinctively what he was asking, and didn't give it a second thought. Until now.
dethwing
DeTheeThaw

 Posted: Wed Jan 18, 2012 4:19 am    Post subject: 10 Then in the second class, someone asked about a different problem. It asked to find all values of d that make the following statement true: 9 | 78,32d The student said he thought it was multiplication by d, instead of being a digit. My immediate response was: despite the fact that there are two numbers to the right of the comma? It doesn't say digit, true, but who puts a comma after 2 digits?
Death Mage
Raving Lunatic

 Posted: Wed Jan 18, 2012 4:40 am    Post subject: 11 "Two days apart" would mean, to me, Tuesday and Thursday, for example. Those are "two days apart"._________________* These senseless ramblings brought to you by Insanity™. If you just can't figure the dang thing out, it must be Insanity™. [YOUR AD HERE!]
Trojan Horse
Daedalian Member

Posted: Wed Jan 18, 2012 6:14 am    Post subject: 12

 dethwing wrote: My immediate response was: despite the fact that there are two numbers to the right of the comma? It doesn't say digit, true, but who puts a comma after 2 digits?

Someone that is using the comma to represent a decimal point. (Some countries do that; they use a period where we use commas, and vice versa.)
Neo
Daedalian Member

Posted: Wed Jan 18, 2012 6:26 am    Post subject: 13

 dethwing wrote: The funny thing is, it's not my wording. I took the class from someone else who has been using this wording for ages. I read it, knew instinctively what he was asking, and didn't give it a second thought. Until now.

Something I learned recently (this week actually) is that it hasn't really been explained why some interpretations of things are just known to be "correct." One example given was "He only drinks red wine." It's an ambiguous sentence, despite having a commonly accepted and "known" interpretation.

In the second case, I could see the student making a case if they were from or in some place that used commas where the US would normally use decimal points, but in my mind that's still rather weak. I wouldn't be inclined to give them that one.
_________________
Ad Astra
MatthewV
Daedalian Member :_

 Posted: Wed Jan 18, 2012 6:41 am    Post subject: 14 I tend to not use commas when handwriting numbers. I learned to put a small amount of space between groups of numbers. For the 9 | 78,32d, I looked around to see where you defined d. And I still have no clue what the | means. So exactly what am I looking for?
dethwing
DeTheeThaw

 Posted: Wed Jan 18, 2012 6:54 am    Post subject: 15 Vertical line means "divides". So 2 | 4.
referee
June 21st, 2004 Member

 Posted: Wed Jan 18, 2012 7:24 am    Post subject: 16 In other words, from numbers between 78320 and 78329 (both included), which ones are divisible by 9?_________________Jan 21st, 2008: The pillaging continues. Mar 4th, 2008: Rest in Peace, Gary Gygax. May your dice always roll a natural 20 wherever you are. Be the Ultimate Ninja! Play Billy Vs. SNAKEMAN today!
Lepton*
Guest

 Posted: Wed Jan 18, 2012 1:00 pm    Post subject: 17 SI/Metric/ISO demands a space to separate the thousands from the hundreds for numbers larger than 9999. ie: 10 000; 999 999; 4444. I've seen some Americans use a comma in numbers like 3333 (making it 3,333) but otherwise I think comma usage simply apes European spacing (10,000; 999,999). For what it's worth, as a Canadian who has done some traveling, I'd have interpreted that comma as a decimal point, and thus misunderstood your question, at least on a first reading.
Jedo the Jedi
Paragon in Training

 Posted: Wed Jan 18, 2012 1:37 pm    Post subject: 18 I don't see why it being a decimal would cause misunderstanding. That would just mean the number to be divided would be smaller. _________________Paragon Tally: 18 mafia, 3 SKs (1 twice), 1 cultist, numerous chat scum...and counting.
extro...*
Guest

Posted: Wed Jan 18, 2012 3:26 pm    Post subject: 19

 Neo wrote: Something I learned recently (this week actually) is that it hasn't really been explained why some interpretations of things are just known to be "correct." One example given was "He only drinks red wine." It's an ambiguous sentence, despite having a commonly accepted and "known" interpretation.

It's more ambiguous than you might think, and it's what makes computer natural language processing so difficult: It requires a lot of "common sense" knowledge about the real world.

"He only drinks red wine", I think, means he doesn't drink white wine, but doesn't exclude that he may drink coffee or tea at breakfast. But alternatively, "He only drinks red wine" could allow that he drinks white wine too. It could mean that the only thing he does with red wine is drink it (he doesn't bathe in it, or brush his teeth with it). "I only charcoal grill my burgers" would be a clearer example of a sentence with similar structure, but interpreted that way (I don't prepare burgers any other way - I might charcoal grill my steaks too).
Chuck
Daedalian Member

 Posted: Wed Jan 18, 2012 4:08 pm    Post subject: 20 "He only drinks red wine" looks like it means no one else drinks red wine.
Neo
Daedalian Member

 Posted: Wed Jan 18, 2012 8:17 pm    Post subject: 21 He only drinks red wine. Only he (and nobody else) drinks red wine. The only action he performs with red wine is drink it. The only alcoholic drink he consumes is red wine. The only red thing he drinks is wine. The only liquid he ingests is red wine. The only thing he ingests (period) is red wine. He does nothing else at all except drink red wine._________________ Ad Astra
MatthewV
Daedalian Member :_

 Posted: Wed Jan 18, 2012 10:33 pm    Post subject: 22 And on another side note: when writing decimal numbers less than one, always add the leading zero. Otherwise, people will commonly not see the decimal point. This is particularly true with single digit decimals. A few months ago I added 10 times too much cobalt carbonate to a glaze recipe because it was written as .5. It was a very rich dark blue that everyone loved (and cost ~\$50 more) Written language should be about clarity first and elegance second.
Jedo the Jedi
Paragon in Training

 Posted: Wed Jan 18, 2012 11:52 pm    Post subject: 23 Sometimes clarity comes through elegance, just probably not in any of the fields you're thinking. _________________Paragon Tally: 18 mafia, 3 SKs (1 twice), 1 cultist, numerous chat scum...and counting.
MatthewV
Daedalian Member :_

 Posted: Thu Jan 19, 2012 12:47 am    Post subject: 24 A cylinder in the vertical arrangement, dances in side another Diameters of 180 mm on one and 181.2 mm on the other Each with a height of 300 mm, these things are really big! So find the viscosity of the separating fluid, it doesn't require trig When torque is 20 Nm is somehow applied or beckoned So the smaller one rotates twice a second!
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