maths revision

IGCSE and GCSE exams are upon us – time to let loose write outs for the most recent papers to help with final revision and checking.  Are these getting harder or am I getting thicker? Files chucked in my exam bucket at

Difference of two squares, staple diet for GCSE maths students, is first proposition in Carr’s book of magic and has ancient geometric roots in Euclid Book II.