12 of 20 Items .... Type: Find the Error

Problems, Questions, and Puzzles to spark discussion and argument in the maths classroom.

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This question is from the NY Regents test, and discussed by Patrick Honner in his long-running series, "Are These Tests Any Good?"

Can your students find what is wrong with it?


How should they fix it?


.: [ALG2], [Mr. Honner], [Find the Error].

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These questions are from the NY Regents test, and discussed by Patrick Honner in his long-running series, "Are These Tests Any Good?".

Can your students find what is wrong with them?



and



.: [ALG], [Mr. Honner], [Find the Error].

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Mathematical Grammar ... I think a comma might be necessary in #2, maybe two of them. What do you think, students?







.: [ALL], [David Wees], [Find the Error].

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Is that diagram correct?

What if the question were \( 13 \div 5 = 2 R3 \)? Could we diagram it in the same way?


.: [PREALG], [T.R.Milne], [Find the Error].

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Seems as though this UHAUL truck got stuck.


Straightforward question: What's the diameter of that culvert?

Argument: What would have been a better way to phrase that sign so this wouldn't happen?



Dimensions


  • Inside dimensions: 14'6" x 7'8" x 7'2" (LxWxH)

  • Mom's Attic: 2'7" x 7'8" x 2'6" (LxWxH)

  • Deck height: 2' 10"

  • Door opening: 7'3" x 6'5" (WxH)

  • Loading ramp width: 2'2"


.: [GEOM], [Reddit], [Find the Error].

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Expand that image to see details. As you peruse the list of values, how far can you get before you reach an inconsistency? Can we figure out what date each of the five pennies showed?




If you knew this was from a college teacher-education professor, would this change your opinion of the work shown in the picture?


.: [STATS], [internet], [Find the Error].

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The day before yesterday Edward was 17. Next year he will be 20. How can that be the case?


.: [LOGIC], [internet], [Find the Error].

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Taken from David Cox, changed just a little:

While I was out, I left a few distance/rate/time problems for students to solve.  Upon my return, I was asking students about the problems and many students had similar responses.

S:  "The Dirt Triangle."
Me:  "?"
S:  "Look, Mr. Cox it's like this...


"...You cover up the one you're looking for and if the other two are next to each other, you multiply.  If one is above the other, you divide."



Me:  "Really? That's strange.  I never learned the Dirt Triangle. I learned ... The Turd Triangle



S1: "No, that won't work. That's not what he told us."
S2: "He said it didn't matter how we wrote it."

Me: "So which is it; does one work or are they the same?  Make your case and be ready to defend it."


.: [PREALG], [internet], [Find the Error].

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Huffington Post:

According to the most recent CDC estimates,
autism spectrum disorder has been identified in about 1 in 88 children, and autism is more likely among boys, among whom prevalence is estimated at 1 in 54.

What does that make the rate for girls?

If the vaccines are the cause, why would there be such a difference between the genders?

If thimerosol (a mercury compound) is the cause, why have the rates of autism RISEN after thimerosol was removed from MMR vaccines?

If the only study to show a link ever done (Wakefield) studied a tremendously small number of kids, was proven to be insurance company scam fraud, was shown to have critical flaws in methodology and analysis, and was proven wrong over and over and over and over again, ....



Kristen Cavalieri:
"There's really scary statistics out there, and to each their own. Autism wasn't prevalent -- like it is now -- years ago, so something is going on, whether it's the chemicals in our food or the vaccines," she continued. "Something is happening, and we can't really ignore that. I choose to believe that I think it's in the vaccines but, again, to each their own and that's where I stand on it."

Let's toss in the Jenny McCarthy Death Count.This is a record of deaths and illnesses that could have been prevented by vaccines but the parents were convinced by Jenny to refrain from damaging their kids.








You can keep up to date with the Jenny McCarthy Body Count.

You can check this data at the CDC's Morbidity and Mortality Reports, if you trust those **scientists**.

You can read the American Academy of Pediatrics summary.




Or you can listen to a woman who has never taken a college-level science class in her life and was so crazy not even Jim Carrey could stand it for long. If you favor the crazy, you can read Jenny's old website
(Internet Archive link) and get insight into her belief that she's an "indigo mom" (sort of a superior species of human) and that her son was special and would have been the start of a more highly-developed race of humans .... until he contracted autism.

(Her son's autism diagnosis has been questioned because she claims that he was cured of it by chelation therapy, the administration of chelating agents to remove heavy metals from the body. If that had worked, we'd probably be using it a lot right now ...)


.: [Politics], [internet], [Find the Error].

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You can tell by the font this is a textbook. You can tell by my tone that this is an error.



.: [ALG1], [T.R.Milne], [Find the Error].

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In a fascinating bit of testimony before a Michigan Senate Hearing, this slide was presented. The presenter (Dr. Ball) asked the legislators to identify where and how the 4th-grade solvers made their mistakes. 



David Wees asks:

"What is the mistake?"
"What is the thinking that led to this mistake?"

I saw both for (b) and (c) but the train of thought in (a) escaped me completely. What do you think happened in (a)?

What would you tell the students in each case?


.: [Teacher Education], [David Wees], [Find the Error].

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SmartBoard software used to come with "cool" demonstrations of a few random math techniques. One of them was this one.

What's your opinion on this?




.: [MS Math], [T.R.Milne], [Find the Error].