Checking Techniques

This is a set of 50+ questions that have been answered incorrectly and for students to spot quickly why the answer given cannot be correct. I have also put some blank slides and templates at the end for people to make their own, as I suspect that I will be constantly adding to it over time. Loads of topics are covered from Number, Algebra, Geometry and Statistics and there is a menu at the start to go directly to the topic you need. I have given the correct answer where appropriate but stopped short of detailed solutions to allow for discussion in class about how you spot the mistake and how you solve the problem. I have removed all the answers for the printable version and converted to PDF should it be useful. It is designed to dip into occasionally, not to be a whole lesson but who knows where things might take you? It was inspired by students constantly asking whether an obviously wrong answer was correct.