This is another task inspired by Dave Taylor’s excellent site Increasingly Difficult Questions. I have ramped up the challenge, significantly as the set progresses. I wanted to include the taking of a bracket as a common factor. This isn’t, of course, a sheet for initial teaching, but more of a review exercise. The questions 23-26 are designed to provoke some discussion (I anticipate them being slightly beyond the level pupils have seen before).

Credit: @chrismcgrane84