I think 'trick' depends on the assumed expectations of the people being asked to answer it. So, for example, if students are expecting to do a straightforward bit of manipulation but there is a zero lurking somewhere (such as when dividing by an expression, or when integrating to find area) then it is a 'trick' but something they ought to be ready for - maybe a 'trip' rather than a trick.
A similar one is used in the CSMS test on people's understanding of place value. The question is about a people-counting clicker device on a turnstile and it reads 6399, so what will it read after the next person has gone through? Whenever I try this out on groups of whatever age and knowledge there are errors - so what can be assumed about people's understanding of place value from this? and what can be assumed about how people rush to conclusions?
-----Original Message----- From: Post-calculus mathematics education [mailto:MATHEDU@JISCMAIL.AC.UK] On Behalf Of Chris Sangwin Sent: 10 September 2010 16:00 To: MATHEDU@JISCMAIL.AC.UK Subject: Trick questions.
I am emailing to ask for some help in identifying "trick questions" in mathematics.
A mathematics question/exercise/task is said to be a "trick question" if the reasoning required to solve it is applicable only to the solution of that question.
I am having some difficulty in identifying "trick questions". For example, the task "Expand (x-a)(x-b)(x-c)...(x-z)" felt to me originally to require a trick. But, on reflection, the reasoning is precisely that needed to construct Lagrange polynomials (HINT!).
Can anyone identify a trick question? I'm struggling to do so.