AS-level maths error: students set impossible question (02 Jun 2011)
Exam question error in AS-level paper (06 Jun 2011)
I sympathise with the people who took those exams, and I don't want to kick anyone while they're down. However, I think there are some general exam techniques that will act as "damage control" in a situation like this. They aren't new, but apparently not everyone knows them.
1. Work out a schedule for the exam, i.e. know how much time you can spend on each question. Once the time's up, move on, even if you haven't finished. You can come back to it at the end if you have time.
Taking the OCR maths exam as an example, there were 72 marks, and people had 90 minutes. (There's a past paper here.) So, keep it simple: 1 minute per mark. (You can round down, but don't round up!) That leaves 18 minutes spare at the end of the exam to check your answers and work on any unfinished questions. Realistically, you can dip into your reserve a bit early if you need to. For instance, if you run out of time for a question but you know that it will only take you another 30 seconds to finish then it's better to keep going while you've got it all in your head.
In this particular exam, the impossible question was worth 8 marks. According to one of the comments, someone spent 40 minutes trying to answer it, and then left other questions unanswered. He should have abandoned it much earlier.
This is a skill that's useful in general life as well. For instance, suppose that my boss gives me a list of 8 bugs to fix in a computer program, and I estimate that it will take me 1 hour for each, i.e. a full day's work. If one of them turns out to be much more complicated than I realised, but they are all equally important, my best approach is to do the other 7 and then tell my boss that I need more time for the 8th. If I go back at the end of the day and tell her that I haven't fixed any of them because I spent all my time on the first, she won't be happy!
2. Don't cross an answer out until you have something better to replace it.
Another comment on the BBC article says: "Having spent a long time on this question I resorted to crossing out all of my working out." This reminds me of one of my maths exams in Durham, at the end of my first year.
I knew that I was going to struggle with this paper, and I actually wound up failing it. (I did resits during the summer.) When I looked through the list of questions, I saw one in particular that looked extremely difficult, so I decided not to even attempt it. About 30 minutes into the exam, one of the lecturers came into the room and made an announcement: "There's a mistake in question 2, and it should say 60 instead of 40." (Or words to that effect.) This didn't make any difference to me, but the guy next to me gave a muffled shriek and crossed out everything he'd just written, holding his pen as if he was stabbing someone. We then all continued in silence. 10 minutes later the lecturer came back and said: "Ok, we've agreed that if you answered the question as it was typed then we'll accept your working." My neighbour then gave a less muffled shriek, and stared at his paper, obviously trying to work out whether he could restore the writing that he'd crossed out. After the exam, I decided that it would be best to give him some space, rather than asking "How did you get on?"
Again, this is a general purpose skill, which is easier to accomplish when you work electronically. For instance, when I was planning my LEJOG trip, I needed to make a few changes to my original route. So, I made a copy of my route, then amended the copy to delete several points and take a different path. I could then compare the two routes, and decide which one to use.