ILiveInFlipFlops Posted February 27, 2016 Share Posted February 27, 2016 Can you solve this math word problem?A length of thread measured 2/7 of a meter long. Mr. Keller used 2/5 of it. How much thread did he have left? I need to see if I'm crazy or Singapore is. Thanks! Quote Link to comment Share on other sites More sharing options...
cintinative Posted February 27, 2016 Share Posted February 27, 2016 (edited) what grade level?? We haven't gotten this far yet, so I am tapping the archives, but I believe you just multiply the fractions. 2/5 of 2/7 is 2/5 * 2/7 or 4/35 ETA: skipped a step original length was 2/7=10/35 original length minus part removed= 10/35-4/35=6/35 thanks to poster after me for reminding me I skipped a step!!!! Edited February 27, 2016 by cintinative 2 Quote Link to comment Share on other sites More sharing options...
DragonFaerie Posted February 27, 2016 Share Posted February 27, 2016 2/5 * 2/7 = 4/35 10/35 - 4/35 = 6/35......maybe. I teach English. :D 2 Quote Link to comment Share on other sites More sharing options...
SparklyUnicorn Posted February 27, 2016 Share Posted February 27, 2016 2/5 * 2/7 = 4/35 10/35 - 4/35 = 6/35......maybe. I teach English. :D That's what I come up with. 4 Quote Link to comment Share on other sites More sharing options...
Daria Posted February 27, 2016 Share Posted February 27, 2016 I agree with DragonFaerie, but I would do the opposite order. 5/5 - 2/5 = 3/5 He has 3/5 of the piece left. 3/5 * 2/7 = 6/35 3/5 of the piece is 6/35 long 3 Quote Link to comment Share on other sites More sharing options...
Arcadia Posted February 27, 2016 Share Posted February 27, 2016 (edited) This 3/5 * 2/7m = 6/35m Because it is easier to do 5/5-2/5 for me Edited February 27, 2016 by Arcadia 2 Quote Link to comment Share on other sites More sharing options...
ILiveInFlipFlops Posted February 27, 2016 Author Share Posted February 27, 2016 OK, that's good enough. Thank you all! That's what both DD and I came up with, and that's what the answer key originally said was correct. However, the list of errata on the Singapore site had me change the correct answer to 4/35. So now their errata need a list of errata! I love Singapore, but I feel like there are so many errors in the books. I needed a reality check on this one. I appreciate the help :thumbup: 3 Quote Link to comment Share on other sites More sharing options...
ILiveInFlipFlops Posted February 27, 2016 Author Share Posted February 27, 2016 (edited) 2/5 * 2/7 = 4/35 10/35 - 4/35 = 6/35......maybe. I teach English. :D I'm a language-oriented mom teaching math to an arts-oriented kid. It's not been an easy path :lol: I've always said I was comfortable teaching through algebra, and then I'd need help. And now that I'm close to algebra...I think I may be out of my depth! I'm having to relearn everything in order to teach it. Edited February 27, 2016 by ILiveInFlipFlops 2 Quote Link to comment Share on other sites More sharing options...
SparklyUnicorn Posted February 27, 2016 Share Posted February 27, 2016 I'm a language-oriented mom teaching math to an arts-oriented kid. It's not been an easy path :lol: I've always said I was comfortable teaching through algebra, and then I'd need help. And now that I'm close to algebra...I think I may be out of my depth! I'm having to relearn everything in order to teach it. I find the wording of their word problems confusing as heck. I don't know if I'm dense or what. 3 Quote Link to comment Share on other sites More sharing options...
ILiveInFlipFlops Posted February 27, 2016 Author Share Posted February 27, 2016 I find the wording of their word problems confusing as heck. I don't know if I'm dense or what. I agree, but I think that's probably intentional, to really make the student work to understand the problem and sort out the parts. At least, that's what I'm telling myself! Quote Link to comment Share on other sites More sharing options...
SparklyUnicorn Posted February 27, 2016 Share Posted February 27, 2016 I agree, but I think that's probably intentional, to really make the student work to understand the problem and sort out the parts. At least, that's what I'm telling myself! I don't know if that is intentional. I've often wondered if it is because they are foreign books. There are some nuanced language differences. Years ago I bought this super mega pack of logic puzzle magazines. They threw in several British books. I sometimes got tripped up on wording even though it is essentially the same language. That's what I tell myself. LOL I have tons and tons of word problem books from all sorts of places and the SM ones are the only ones I had that kind of hard time with. I don't even use them with my second kid. I had enough of those books. 2 Quote Link to comment Share on other sites More sharing options...
Ausmumof3 Posted February 27, 2016 Share Posted February 27, 2016 No you're not crazy. We've come across a few errors as well though I must admit I tend to not use the answer guide too much where I'm already comfy with the work. I live Singapore but my kids hate the way it's written. We've only got one more year to go though so I don't want to switch now. 1 Quote Link to comment Share on other sites More sharing options...
Daria Posted February 27, 2016 Share Posted February 27, 2016 Word problems that have no real world context make my head spin. Why would you have 2/7 of a meter of something? How would you know it was 2/7? I've never had a meter stick that was marked off in sevenths . . . I was working with a student today, not on Singapore, but we kept hitting word problems that said things like: Johnny went into his family's garage. He saw screwdrivers, nails and garden rakes. He made a graph of what he saw . . . OK, first of all, who goes into their garage and makes a graph of what they see? Secondly, did his garage only contain those 3 random items? Did he really own 12 screwdrivers and no screws, just nails? 4 garden rakes and not one shovel? Or did he just graph his favorite things? 10 Quote Link to comment Share on other sites More sharing options...
SparklyUnicorn Posted February 28, 2016 Share Posted February 28, 2016 (edited) Word problems that have no real world context make my head spin. Why would you have 2/7 of a meter of something? How would you know it was 2/7? I've never had a meter stick that was marked off in sevenths . . . Yes I hate that too. That problem isn't too terrible, but some of them. What the what what. "Gina is 5 years older than her dead pet hamster, how old is Ralph's sister?" I don't know, but I now hate Gina, her dead pet hamster, Ralph, his sister, AND now math. Edited February 28, 2016 by SparklyUnicorn 12 Quote Link to comment Share on other sites More sharing options...
ILiveInFlipFlops Posted February 28, 2016 Author Share Posted February 28, 2016 Word problems that have no real world context make my head spin. Why would you have 2/7 of a meter of something? How would you know it was 2/7? I've never had a meter stick that was marked off in sevenths . . . I was working with a student today, not on Singapore, but we kept hitting word problems that said things like: Johnny went into his family's garage. He saw screwdrivers, nails and garden rakes. He made a graph of what he saw . . . OK, first of all, who goes into their garage and makes a graph of what they see? Secondly, did his garage only contain those 3 random items? Did he really own 12 screwdrivers and no screws, just nails? 4 garden rakes and not one shovel? Or did he just graph his favorite things? Yes I hate that too. That problem isn't too terrible, but some of them. What the what what. "Gina is 5 years older than her dead pet hamster, how old is Ralph's sister?" I don't know, but I now hate Gina, her dead pet hamster, Ralph, his sister, AND now math. :smilielol5: :smilielol5: :smilielol5: 1 Quote Link to comment Share on other sites More sharing options...
trulycrabby Posted February 28, 2016 Share Posted February 28, 2016 (edited) I remember that problem! :ack2: Edited February 28, 2016 by trulycrabby 1 Quote Link to comment Share on other sites More sharing options...
Garga Posted February 28, 2016 Share Posted February 28, 2016 Word problems that have no real world context make my head spin. Why would you have 2/7 of a meter of something? How would you know it was 2/7? I've never had a meter stick that was marked off in sevenths . . . I was working with a student today, not on Singapore, but we kept hitting word problems that said things like: Johnny went into his family's garage. He saw screwdrivers, nails and garden rakes. He made a graph of what he saw . . . OK, first of all, who goes into their garage and makes a graph of what they see? Secondly, did his garage only contain those 3 random items? Did he really own 12 screwdrivers and no screws, just nails? 4 garden rakes and not one shovel? Or did he just graph his favorite things? Yes I hate that too. That problem isn't too terrible, but some of them. What the what what. "Gina is 5 years older than her dead pet hamster, how old is Ralph's sister?" I don't know, but I now hate Gina, her dead pet hamster, Ralph, his sister, AND now math. I haven't laughed so hard all month. Thanks guys! I don't usually get tripped up with the details like you're saying above, but my kids sure do. I see where they're coming from now. 3 Quote Link to comment Share on other sites More sharing options...
Garga Posted February 28, 2016 Share Posted February 28, 2016 Word problems that have no real world context make my head spin. Why would you have 2/7 of a meter of something? How would you know it was 2/7? I've never had a meter stick that was marked off in sevenths . . . I was working with a student today, not on Singapore, but we kept hitting word problems that said things like: Johnny went into his family's garage. He saw screwdrivers, nails and garden rakes. He made a graph of what he saw . . . OK, first of all, who goes into their garage and makes a graph of what they see? Secondly, did his garage only contain those 3 random items? Did he really own 12 screwdrivers and no screws, just nails? 4 garden rakes and not one shovel? Or did he just graph his favorite things? Johnny needs to have a yard sale. 3 Quote Link to comment Share on other sites More sharing options...
Daria Posted February 28, 2016 Share Posted February 28, 2016 Johnny needs to have a yard sale. If Johnny has a yardsale and sells 11 screwdrivers for $2.94 each, how many screws can he purchase, if screws cost $3.75 a lb, and weigh .025 oz each? 7 Quote Link to comment Share on other sites More sharing options...
ILiveInFlipFlops Posted February 28, 2016 Author Share Posted February 28, 2016 If Johnny has a yardsale and sells 11 screwdrivers for $2.94 each, how many screws can he purchase, if screws cost $3.75 a lb, and weigh .025 oz each? He sold all his screwdrivers, so what does he need with screws?! It's a moo point :D 2 Quote Link to comment Share on other sites More sharing options...
Daria Posted February 28, 2016 Share Posted February 28, 2016 He sold all his screwdrivers, so what does he need with screws?! It's a moo point :D No he has one left! Of course, doofus that he is he'll probably keep the Phillips heads and buy the screws for a flat head. The more important question is: If Doofus Johnny wastes a whole day on a yard sale, full of visitors who track mud all over the carpet, and still doesn't end with the tools he needs to fix the disposal, how many nights will his husband Fred make him sleep on the couch? 5 Quote Link to comment Share on other sites More sharing options...
ILiveInFlipFlops Posted February 28, 2016 Author Share Posted February 28, 2016 No he has one left! Of course, doofus that he is he'll probably keep the Phillips heads and buy the screws for a flat head. The more important question is: If Doofus Johnny wastes a whole day on a yard sale, full of visitors who track mud all over the carpet, and still doesn't end with the tools he needs to fix the disposal, how many nights will his husband Fred make him sleep on the couch? Ah, word problems for our modern society :lol: 2 Quote Link to comment Share on other sites More sharing options...
Tanaqui Posted February 28, 2016 Share Posted February 28, 2016 No he has one left! Of course, doofus that he is he'll probably keep the Phillips heads and buy the screws for a flat head. The more important question is: If Doofus Johnny wastes a whole day on a yard sale, full of visitors who track mud all over the carpet, and still doesn't end with the tools he needs to fix the disposal, how many nights will his husband Fred make him sleep on the couch? He won't be getting any screws until he stops sleeping on the couch. Because he's stubborn like that. 1 Quote Link to comment Share on other sites More sharing options...
Joyofsixreboot Posted February 29, 2016 Share Posted February 29, 2016 I find the wording of their word problems confusing as heck. I don't know if I'm dense or what.Um. Yeah, because I figured out how many cm he had left, then read the answers and was like, oh, they just wanted the fraction. 1 Quote Link to comment Share on other sites More sharing options...
Ausmumof3 Posted February 29, 2016 Share Posted February 29, 2016 This whole thread is hilarious. Maths class gone wild. 1 Quote Link to comment Share on other sites More sharing options...
JanetC Posted February 29, 2016 Share Posted February 29, 2016 “Only in word problems can you buy 60 cantaloupes and no one asks what the heck is wrong with you.†https://www.noodle.com/articles/why-math-word-problems-fail-and-how-we-can-get-them-right238 Best real world math problems (middle school and up): http://www.wyrmath.com/ Quote Link to comment Share on other sites More sharing options...
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