Jump to content

Menu

What kind of mindbending insanity is this problem??


ktgrok
 Share

Recommended Posts

This is in a 5th grader's homework. This is not a joke, this is the actual problem. (As soon as I saw that the side marked 42 was smaller than the side marked with the 10 and 7 I got angry and lost faith in public education and it sort of spiraled from there....)

RenderedImage.thumb.jpeg.856f805df16db38ed4519db1f0b916bf.jpeg

Link to comment
Share on other sites

Just now, Carol in Cal. said:

By analogy, the answer is C.

But the problem itself is way into trick question territory.  AND FOR WHAT?  REALLY, FOR WHAT?

I’m with you, KTGROK.  This is BS.

Well, it seems like 0 =294 - 294, so it feels like 294 should be the value of the expression in the box. I do think I know what they are doing her (provided I got the answer right.) 

Link to comment
Share on other sites

I would assume that the 5th grader would have been taught how to use area models and would have quickly known that B is the answer.  

I didn’t have any problem with it, but I will admit that I taught 4th grade math for many years and taught area models. I would actually call the the partial quotients method though. The Fact that the sides are not in correct proportions also is not a problem for me. When kids are drawing their own, I don’t want them to get bogged down with the idea that the boxes have to be “perfect”. 
 

I get frustrated by parent responses such as in this thread. Just because the parent does not understand does not make the method bad, but it takes a teacher who understands it and can explain it well to parents. I used to hold parent math classes just for that purpose, but I never had more than 1 or 2 attend. Those that did attend were appreciative.

The more “traditional”  methods work great for many people, but others need more time with these longer methods before transitioning to traditional algorithms. 
 

 

Edited by City Mouse
  • Like 5
  • Thanks 1
Link to comment
Share on other sites

Answer is B

Students are supposed to multiply by 10 first (cause it is easy...)

42 X 10 = 420

Now they subtract that from original and get 294

714-420 = 294

Not many 5th graders know that 42 x 7 is 294...

This model's logic is flawed if it is supposed to be easier than using good old long division (that is based on PLACE VALUE).

Perhaps this type of modeling helps ONE student out of hundreds...  so much for the rest of the class.

 

Edited to add that this model DOES represent place value-- but does nothing to help the student solve the problem other than have them dividing by a smaller value.  It DOES represent the place value of the answer 17    (10 and 7)

I've seen them before but there are so many better models out there that actually TEACH... this just wastes time and frustrates students and parents.

 

Edited by Jann in TX
  • Like 13
  • Thanks 1
Link to comment
Share on other sites

2 minutes ago, Jann in TX said:

Answer is B

Students are supposed to multiply by 10 first (cause it is easy...)

42 X 10 = 420

Now they subtract that from original and get 294

714-420 = 294

Not many 5th graders know that 42 x 7 is 294...

This model's logic is flawed if it is supposed to be easier than using place value and good old long division.

Perhaps this type of modeling helps ONE student out of hundreds...  so much for the rest of the class.

Yeah, I'm not seeing how this is any better than place value. I think they are just using it to help visualize the distributive property?? 

  • Like 4
Link to comment
Share on other sites

6 minutes ago, Jann in TX said:

Edited to add that this model DOES represent place value-- but does nothing to help the student solve the problem other than have them dividing by a smaller value.  It DOES represent the place value of the answer 17    (10 and 7)

I mean, it's a bit easier to divide 294 than the original number. That's the number you'd wind up getting if you did long division anyway... and it's not unreasonable to have a kid know that 5*42 = 210. So you could use that to figure out that 7*42 = 294. 

Edited by Not_a_Number
Link to comment
Share on other sites

Any method that goes against 'traditional' math is celebrated as 'new and improved'...   I honestly don't get it.

As a homeschool mom my children had NO issues visualizing multiplication and division using a few straws...  it easily translated to long multiplication and long division (traditional method) and we went on with our lives. (both kids graduated college with honors and are happy adults!).

  • Like 11
  • Thanks 1
Link to comment
Share on other sites

12 minutes ago, City Mouse said:

The more “traditional”  methods work great for many people, but others need more time with these longer methods before transitioning to traditional algorithms. 

I'm actually a radical non-traditionalist, but I don't see this as a helpful visual. It always seems to me that kids wind up doing this kind of method by rote just like they do the more traditional stuff by rote. That's because it's quite inflexible. 

  • Like 6
Link to comment
Share on other sites

I have no idea what an area model is and I've never seen this kind of problem before but I just looked at that pieces of information that were given in the other boxes and by following the patterns I figured the answer was B.  I didn't find it hard but I love problems that require you to figure out the pattern/puzzle so it may just be that I'm wired in such a way that I found this easy. But I also don't see where this is a useful way to teach kids to solve a problem.

Edited by cjzimmer1
Link to comment
Share on other sites

Just now, cjzimmer1 said:

I have no idea what an area model is and I've never seen this kind of problem before but I just looked at that pieces of information that were given in the other boxes and by following the patterns I figured the answer was B.  I didn't find it hard but I love problems that require you to figure out the pattern/puzzle so it may just be that I'm wired in such a way that I found this easy.

I didn't have a ton of trouble figuring it out... I just found the whole thing an unhelpful way to think of division 😛 . 

  • Like 4
Link to comment
Share on other sites

16 minutes ago, City Mouse said:

I would assume that the 5th grader would have been taught how to use area models and would have quickly known that B is the answer.  

I didn’t have any problem with it, but I will admit that I taught 4th grade math for many years and taught area models. I would actually call the the partial quotients method though. The Fact that the sides are not in correct proportions also is not a problem for me. When kids are drawing their own, I don’t want them to get bogged down with the idea that the boxes have to be “perfect”. 
 

I get frustrated by parent responses such as in this thread. Just because the parent does not understand does not make the method bad, but it takes a teacher who understands it and can explain it well to parents. I used to hold parent math classes just for that purpose, but I never had more than 1 or 2 attend. Those that did attend were appreciative.

The more “traditional”  methods work great for many people, but others need more time with these longer methods before transitioning to traditional algorithms. 
 

 

I don’t mind using new methods, but I do mind having to provide homework help and not being able to figure out something from the purchased textbook.  That is what happened when DD was in geometry in high school—the text book was not fully explanatory.  You had to ‘catch’ the usable knowledge in class, and if you didn’t, there was no way to look it up.  That’s just wrong.

  • Like 4
Link to comment
Share on other sites

1 minute ago, cjzimmer1 said:

I have no idea what an area model is and I've never seen this kind of problem before but I just looked at that pieces of information that were given in the other boxes and by following the patterns I figured the answer was B.  I didn't find it hard but I love problems that require you to figure out the pattern/puzzle so it may just be that I'm wired in such a way that I found this easy.

I could not even parse the language. "belongs in the area model representing"? How is this even an "area model"?

  • Like 4
Link to comment
Share on other sites

1 minute ago, regentrude said:

I could not even parse the language. "belongs in the area model representing"? How is this even an "area model"?

I think those are supposed to be the sides of the rectangle. Except that they look totally off and they are so full of numbers that I doubt it's helping anything click for kids. 

  • Like 1
Link to comment
Share on other sites

12 minutes ago, Not_a_Number said:

I think those are supposed to be the sides of the rectangle. Except that they look totally off and they are so full of numbers that I doubt it's helping anything click for kids. 

But how do they represent the areas when they are not proportional and when both rectangles have the same size?
How is a long side representing "10" and a much shorter side representing "42" any help?

Btw, I just showed the problem to my DH. Theoretical physicists, researcher, does math all day. He read the words and said he doesn't even understand what the sentence is supposed to mean.

ET: teachers, pretty please, teach the kids to actually do division. In a way that translates to algebraic expression.

Edited by regentrude
  • Like 13
  • Thanks 3
Link to comment
Share on other sites

Just now, regentrude said:

But how do they represent the areas when they are not proportional and when both rectangles have the same size?

Btw, I just showed the problem to my DH. Theoretical physicists, researcher, doe math all day. he read the words and said he doesn't even understand what the sentence is supposed to mean.

Well... don't ask me, lol. That's just what it's SUPPOSED to do. 

Now I'm curious if my mathematician husband can figure this out 🤣

  • Like 1
Link to comment
Share on other sites

1 minute ago, regentrude said:

 

Btw, I just showed the problem to my DH. Theoretical physicists, researcher, doe math all day. he read the words and said he doesn't even understand what the sentence is supposed to mean.

 

That makes me feel a little bit better!

  • Like 3
Link to comment
Share on other sites

The area model is where they draw rectangles on graph paper that represents adding together the parts — again as a way to represent the multiplication algorithm.

I am not defending it — I have just seen it before lol.  
 

Honestly in general it seems fine to me — like kids who have been shown this stuff aren’t confused by it.  
 

But I don’t know a lot about it.  

Link to comment
Share on other sites

So I stopped about 18 months ago, but I specifically spent time every fall since they announced common core math was on Khan Academy working through all the terms of elementary math just so I could be sure I understand this kind of thing.  And I have no idea. I’d be frustrated too.  

  • Like 2
Link to comment
Share on other sites

Just showed it to dh. I kind of new what they were getting at, but OY, not efficient and definitely convoluted.

Dh and a bachelor's degree in mathematics, some master's level math research coursework, and has been a database architect for what seems like forever. His response, "Please tell me this is NOT how they are attempting to teach division to little kids!"  So ya.

This is just not a clear and concise way to teach the concept.

  • Like 9
  • Haha 1
Link to comment
Share on other sites

1 minute ago, Faith-manor said:

Just showed it to dh. I kind of new what they were getting at, but OY, not efficient and definitely convoluted.

Dh and a bachelor's degree in mathematics, some master's level math research coursework, and has been a database architect for what seems like forever. His response, "Please tell me this is NOT how they are attempting to teach division to little kids!"  So ya.

This is just not a clear and concise way to teach the concept.

This is NOT how they are attempting to teach division to little kids. Actually, they are also teaching it in 6 other ways at the same time, probably, LOL. 

  • Haha 4
Link to comment
Share on other sites

The area model is where they draw rectangles on graph paper and add up the areas of the rectangles.  It also is supposed to show the concept of the multiplication algorithm, I think.  
 

I had it shown to me (by a teacher) with a 1 digit times two digit.

If you have 9 times 36, you have 9 times 30, plus 9 times 6. Then you get 270 plus 54.  
 

I don’t quite know how to do it just like on this worksheet — but it was okay when someone explained that to me, and then that was exactly how that teacher did it.  


 

 

Link to comment
Share on other sites

1 minute ago, Not_a_Number said:

This is NOT how they are attempting to teach division to little kids. Actually, they are also teaching it in 6 other ways at the same time, probably, LOL. 

But this is 5th grade , so apparently all these prior attempts haven't been terribly successful 

  • Like 4
  • Haha 4
Link to comment
Share on other sites

45 minutes ago, cjzimmer1 said:

I have no idea what an area model is and I've never seen this kind of problem before but I just looked at that pieces of information that were given in the other boxes and by following the patterns I figured the answer was B.  I didn't find it hard but I love problems that require you to figure out the pattern/puzzle so it may just be that I'm wired in such a way that I found this easy. But I also don't see where this is a useful way to teach kids to solve a problem.

Yeah, I figured the answer out as well - but I had no idea what the answer had to do with the original problem, lol. So..sort of defeats the purpose if it was supposed to help me solve the original problem. I just did it like an analogy. 

45 minutes ago, Not_a_Number said:

I didn't have a ton of trouble figuring it out... I just found the whole thing an unhelpful way to think of division 😛 . 

Unhelpful is putting it mildly, lol. I think I actually UNlearned division looking at this. 

5 minutes ago, Lecka said:

The area model is where they draw rectangles on graph paper and add up the areas of the rectangles.  It also is supposed to show the concept of the multiplication algorithm, I think.  
 

I had it shown to me (by a teacher) with a 1 digit times two digit.

If you have 9 times 36, you have 9 times 30, plus 9 times 6. Then you get 270 plus 54.  
 

I don’t quite know how to do it just like on this worksheet — but it was okay when someone explained that to me, and then that was exactly how that teacher did it.  


 

 

Right - I know how to do that thanks to Khan academy. But...in those instances, the area shown matches the numbers! This has boxes that have NO relation to the numbers, which is totally confusing. 

I can do an area model - this is not that. This is the bastard child of a bar model, an area model, a Sudoku puzzle, and an SAT analogy. 

Edited by ktgrok
  • Like 3
  • Haha 8
Link to comment
Share on other sites

Just now, ktgrok said:

eah, I figured the answer out as well - but I had no idea what the answer had to do with the original problem, lol. So..sort of defeats the purpose if it was supposed to help me solve the original problem. I just did it like an analogy. 

I think they are just mixing things up. Your draw the rectangles to help you remember the area model, then you put the subtractions inside the rectangles to... save space??? I have no idea. 

Link to comment
Share on other sites

2 minutes ago, Not_a_Number said:

This is NOT how they are attempting to teach division to little kids. Actually, they are also teaching it in 6 other ways at the same time, probably, LOL. 

I would hope. But, I don't have a lot of confidence. Our district spends so much of the school day on standardized test prep, and guessing probable answers not actually solving problems. I think they believe filling in bubble sheets is a hot commodity skill in the future.

Link to comment
Share on other sites

Okay, I think it is set up like the box method for multiplication.

So — the 10 and 7 mean the answer is 17.  They are showing “42 times 17” with the top line of the box.  
 

That is just how the box method is for multiplication.  
 

The box method and the area model often go together but not always.  (Edit:  at least I don’t think this shows an area model — I think it shows the box method?). 

Edited by Lecka
Link to comment
Share on other sites

2 minutes ago, Lecka said:

 

The box method and the area model often go together but not always.  (Edit:  at least I don’t think this shows an area model — I think it shows the box method?). 

This makes more sense (not that that is saying much!) but they labeled it an area model, so?

I think the best and most charitable explanation is the person who wrote this was drunk. 

It's either that, or russian bots are now creating our kids' math curriculum in order to gain superiority. 

  • Haha 10
Link to comment
Share on other sites

1 minute ago, ktgrok said:

This makes more sense (not that that is saying much!) but they labeled it an area model, so?

I think the best and most charitable explanation is the person who wrote this was drunk. 

It's either that, or russian bots are now creating our kids' math curriculum in order to gain superiority. 

Hey now, that Russian Bot thing could be it!!! 😂

  • Like 3
Link to comment
Share on other sites

My poor relative is now wishing they had not sent me their child's math problem...my rant was a bit beyond what they expected, lol. 

At least venting about the failings of modern education has distracted me from my house hunting drama, lol. 

  • Like 10
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...