Actually part of my aim for this thread wasn't to get solutions by the easiest possible means (although at times in revision that was all I cared about) but more to try to get the first years thinking and working together because teachers don't shut up about how working like that helps students to understand. Of course the help is appreciated but being pointed in the right direction can lead to a better understanding. I guess with the amount of questions on the thread though it would take way too long unless people understood their first hint.
Meh, either way works for me, my memory hasn't failed me yet.