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Singapore Math

Showing posts with label problem posing. Show all posts
Showing posts with label problem posing. Show all posts

Monday, October 16, 2023

A Singapore Grade 4 Geometry Question

On Facebook, someone recently posted the above primary 4 (or grade 4) geometry question, asking for help from fellow parents. How would you do it (without calling on ChatGPT)?

If you’re a parent, homeschooler, or tutor, how would you explain it to an eight- or nine-year-old child, who’s struggling with non-drill-and-kill questions on area and perimeter?

Give It a Try First!

Try figuring out the answer on your own first before peeping at two parents’ quick-and-dirty solutions below. Better still, could you present an idiot-proof or peasant-friendly solution that even a smart dog or cat could understand?


 Solution by Belinda Sim


Solution:

6 width and 6 long = 3units  of the rectangle.

1 rectangle -> 16cm.

3 rectangle 

16x3 = 48cm.



Solution by Jesline Ang

Stretch Your Mind!

Many moons ago, I was commissioned to write Mind Stretchers 2*, a grade 5 problem-solving math book, which was popular in a number of local schools and tuition centers—disturbingly, they’re guiltlessly or blatantly photostating entire chapter questions as part of their worksheets.

And I still recall that on the topic of Perimeter, I’d posed a number of routine and nonroutine questions. What surprised or tickled me then was when the Managing Editor asked me whether or not some of these questions are solvable, because at first glance, they look like there are missing information to solving them.

These geometry questions can give students (and probably their oft-math-anxious parents and teachers) some goose pimples out of fear or panic if they can’t figure out the answers offhand. 

Understandably, without a cool mind and some patience (or perseverance), even perimeter and area questions at the elementary (or olympiad) level can prove to be a challenge to math educators if they’re not trained to tackling them using the right approach.

Frustration and fear usually set in, especially for nonroutine questions that don’t normally appear in drill-and-kill school textbooks and workbooks.

Premature Testing

The danger of setting these types of brain-unfriendly questions too early, or having them prematurely in a class test, especially when most students have yet to fully grasp the concepts of area and perimeter, could be detrimental to the mental health of most average math students.

Parents who freeze at the sight of these questions would often exhibit a knee-jerk reaction, by getting a tutor for their child, if they’d afford it.

Tuition or No Tuition?

Most stressed parents often reason that if they couldn’t even solve these grade 4 questions, things would only get worse in later years, as the higher-grade topics get more complicated and the questions become more challenging. They just don’t want to see their child struggle in math, especially when they themselves had had a negative experience of the world’s most disliked school subject.

Even for math teachers and tutors, there’s nothing to be ashamed of if at first or second reading, they’re clueless how to tackle these nonroutines. Yes, they do appear in mid- or final-year exams arguably as a social filter to separate the nerd from the herd, but once math educators and homeschoolers know how to approach these questions from the right angle, before long, these math problems would become routine to them.

The 4F’s of Mathematical Problem Solving

Few math teachers and writers would admit that (school or olympiad) math involves lots of fears, false starts, frustrations, and failures. The sooner parents and homeschoolers (and their children and grandchildren) are aware of this oft-unspoken problem-solving process or ritual, the pressure or expectation level for all parties ought to go down significantly in reducing any unnecessary mental or mathematical stress.

Pain is (always) part of the joy of creative mathematical problem solving—the no-pain-no-gain mantra is axiomatic in math at all levels.

Geometrically & perseveringly yours

© Yan Kow Cheong, October 16, 2023.

* When the wallet-friendly title was out of print, a senior editorial staff emailed me that he’d pay me a cosmetic S$150 to buy the copyrights. I never bothered to reply to his laughably ridiculous suggestion. I wouldn’t be surprised that they’d since plagiarized the content to be used and reused for other purposes.

Friday, May 19, 2023

Creativity or Stupidity?


This week, I saw this attached (grade one?) test item or math meme on Facebook, which was initially posted by “The Language Nerds” group.

Based on the multiple comments to this ill-posed math question, it’s amusing, yet also disturbing, to read that most responders are praising the student for his “creative” answer, or criticizing the “uncreative” teacher for penalizing the poor child.

In this postmodern or polarized world we’re living in, you’d think that maybe only someone who’s a “very stable genius” would rationalize or argue that the student’s response qualifies as one of the equally valid answers. And if the biased teacher insisted on marking the creative child wrong, the parents might consider suing him or her for giving their son an undeserved zero.


Creative or Uncreative Comments

Below are some netizens’ replies to the math question from “Maths Jokes Daily,” which range from the hilarious to the ridiculous to the preposterous.

I think because the circles weren't closed properly 🤔

honestly think its possible for most people to understand what you are supposed to do here, so I would definetely argue that this is not a badly formed question :)

Were the correct answers 1.39, 2.17 and 3.96 ?

He got it wrong because he marked 3 numbers, and the question only asked for one, so the right answer is 15

He provided 3 right answers. He identified the smallest number in each row disregarding the periods and commas. LOL !

He circled 3 numbers. Number 1 is the smallest number and therefore should have only selected the 1 single number.

Also, why did the teacher put 3 lowercase "alpha" symbols?🤣

it’s evident smallest number and not smallest numberS so he should have circled only 1

Because he only circles 1 but not 1.39 Same with others

The fault lies entirely with the fool that numbered the questions with Roman Numerals and then used 1, 2, 3 instead of a, b, c

That kid is already smarter than the teacher.

Thats at least .5 for thinking outside the box

? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! ? ! 


Would you side with the teacher or the student? How would you respond to the “wrong” answer to this ill-posed or improperly posed question?

Creatively or uncritically yours

© Yan Kow Cheong, May 19, 2023.

Thursday, August 1, 2013

To Count or Not to Count

Einstein said, "Not everything that counts can be counted, and not everything that can be counted counts."


One of my favorite childhood games!
Five stones or five bags containing rice
.
Here are a dozen math questions that you may pose to your grades 2–3 child to see whether they've graduated from rote-learning, ready to tackle higher-order thinking questions. Don't ignore their answers off-hand, silly as some of them may appear to be. Use them to question the reasonableness of their thinking processes, or to promote sense making in problem solving.

Questions crying to be solved

1. Farmer Jones had 220 goats: 65 he-goats and 155 she-goats. 100 goats died last winter. How many he-goats did he have left?

2. Film A is only 94 minutes long. Film B is 1 hour 40 minutes. Which film is better? Explain.

\3. The largest painting in museum P is 60 centimeters square; the one in museum Q is one and a half times bigger. Which museum is worth visiting? Why?

4. There are 125 sheep and 5 dogs in a flock. How old is the shepherd?

5. If one Mona Lisa painting is worth $12 million, how much will two such paintings be worth?

6. Mr. Smoth has two children: a 9-year-old son and a 12-year-old daughter. How old is the mother?

Creative logic ©1999 The Straits Times & A. Choy 

7. A fake Rolex watch costs $2,500 at a shop in Dubai. How much would four such watches cost a businessman from a developing country, if he were to buy the original ones?

8. There are 26 sheep, 12 pigs, and 14 goats on a ship. How old is the captain?

9. Yesterday 37 boats sailed into port and 49 boats left it. Yesterday at noon there were 43 boats still in the port. How many boats were still in the port yesterday evening?

10. Tom used to have 45 Facebook friends. After some friends unfriended him for forwarding their personal e-mails without their permission, Tom is now left with 51 friends. How many friends left him?

11. On Tuesday, at 4:00 PM, Sherry was overjoyed when she had seven new Twitter followers. However, the next day, three of them unfollowed her. How many Twitter followers does she have now?

12. Ken received 8 new e-mails today. After deleting some of his e-mails, his inbox was left with 21 of them. How many e-mails were in his inbox at first?

0 friends, 3000+ Facebook friends, fiends, and foes
© 2011 Tanya Cooke

Creative problem posing 

Use these "insensible" or "unreasonable" questions to get the children to amend them, before they're deemed "solvable." Let their creative imagination run wild by posing their own versions; and be prepared for some surprises in their responses. You may be astounded how their literacy and numeracy grow by leaps and bounds.

Happy problem posing and problem solving.


References
Cooke, T. (2011). Help! I'm a Facebookaholic. London: John Blake Publishing Ltd.
Schoenfeld, A. H. (2012). A modest proposal. Notices of the AMS, 59(2), 317-319.
Yan, K. C. (2012). Mathematical quickies & trickies. Singapore: MathPlus Publishing.

© Yan Kow Cheong, August 1, 2013.