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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WitCH 81: Pointed Criticism

This is another one courtesy of Mysterious Michael. We’re not quite sure whether it’s a WitCH, or a PoSWW, or one for the error list, or simply a roll-your-eyes-and-ignore. In any case, it’s a question from the notorious 2016 Methods Exam 2 (report here), and we’ve expanded slightly from MM’s stated concern. (We could’ve expanded to include the entire question, as a Road to Nowhere, but decided not to lose too much of MM’s original focus.)

Have fun.

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WitCH 79: Cos Why Not?

Yeah, we’re busy, but this one has been bugging us. It is an exercise and solution from Cambridge Specialist Mathematics 3&4. It’s basically a PoSWW, or we could simply let it pass as a textbook glitch. But we think there’s more than the obvious to say.

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WitCH 77: Road to Nowhere

If nothing else, people can enjoy a great song.

This one puzzled us when we gave the 2021 Further Mathematics Exams a three-minute scan, but we didn’t bother then to think, um, further. Now, however, since graph theory is likely a mandatory part of Specialist 1&2, and thus also, at least technically, a mandatory part of Specialist 3&4, we have thought a little harder. So, after discussions with John Friend and with a colleague who we shall refer to as Professor Combo, here we are.

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