Witch 96: Root Con All

This is the fourth of our three WitCHes on VCAA’s Specialist Mathematics Exam 1 Sample Questions. Yeah, yeah it’s Douglas Adams-ish, but it wasn’t deliberate. We were undecided on this last one, and it’s not as compelling as the others. But, for similar reasons for the other WitCHes, we changed our mind and decided to post it. (There were other close calls, and we’ll soon update this post with brief comments on all the questions.)

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Witch 95: Top of the Pops

This is the third of our three WitCHes on VCAA’s Specialist Mathematics Exam 1 Sample Questions. Newcomer aps was first to comment on the error, in regard to VCAA’s webinar, where the same question is “solved” (and see the subsequent comments on that post). Once again, it seems worthwhile to encourage a prominent discussion on an unfamiliar topic, and there is more to say than has come up so far.

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Witch 94: What Are the Odds?

This is the second of our three WitCHes on VCAA’s Specialist Mathematics Exam 1 Sample Questions. It may not be quite bad enough for a WitCH, but it’s very not good. Our main reason for posting it is because we believe there is more in the question than might meet a teacher’s eye. As with our previous WitCH, this question is on a new topic, and some visible discussion seems worthwhile. Continue reading “Witch 94: What Are the Odds?”

Witch 93: Base Balls-Up

This is the first of three WitCHes on VCAA’s Specialist Mathematics Exam 1 Sample Questions. We spent a solid hour writing a critique of this one, and another half hour removing the bad language. Given the topic is new, however, and will be not so familiar to many teachers, we decided the question required more prominence, and proper discussion. The question was first flagged by commenter Michael, and the sample questions have been discussed generally on this post and this post. Continue reading “Witch 93: Base Balls-Up”

WitCH 92: The Webs VCAA Weaves

This is a continuation of a previous WitCH. To provide teachers with some guidance on the new VCE Specialist Mathematics curriculum (Word, idiots, and see comments here), VCAA had posted two webinars, on proof by contradiction and proof by induction; we WitCHed it. VCAA has now added four new webinars, which can be viewed here, and with companion documents as indicated below.

Get to work.

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WitCH 90: Tiles and Tribulations

This is late, and it isn’t very Christmasy. But it came up as part of another project, and it’s been bugging us, so Bah Humbug.

The following is a question from 2022 Mathematical Methods Exam 1. It’s been discussed some on this post, including a concerning rumour (edited 24/12/22), and we also hammered some of the wording on this post. It is clearly deserving of its own WitCH.

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WitCH 89: Proof Negative

VCAA’s new version of Specialist Mathematics contains “Proof” as a topic (which says everything one needs to know about VCE mathematics). A few commenters have alerted us to the fact that VCAA have now provided two videos: on induction (transcript and slides); and on proof by contradiction (transcript and slides). There are issues.

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WitCH 88: Unwarranted Confidence

One more from the 2022 Specialist Mathematics Exam 2. Belatedly, we’ve decided this one deserves its own post. It’s probably more of a PoSWW. But, for those weirdos who like to think about this stuff, there are probably also aspects to discuss.

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WitCH 87: Cannery Row

(The title is very clever, but you have to think about it.)*

This one is the last part of the last question of 2022 Specialist Mathematics Exam 2 (not online). It sparked a lot of discussion on the exam post, but seems worth its own WitCH. The question is clearly a mess, but what was intended, and how to think about the mess is not so clear, at least to us. (We showed the question to a professor of statistics, whose first reaction was “Ow!” We’ve applied the smelling salts, and we should be in possession of the professor’s second reaction soon.)

For clarification, we are (kinda sorta) told in the question stem that the masses of the empty cans are normally distributed, but we are told nothing else relevant, other than what’s given below.

Go for it (again).

*) Proving that the title is not really that clever.

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