D=x+ytD = x + ytD=x+yt
x=40x = 40x=40 y=15y = 15y=15 t=3t = 3t=3
Work out the value of DDD.
Practise Edexcel GCSE Maths Substitution with exam-style questions for Foundation and Higher tier. 100 questions, matched to the Edexcel GCSE Maths (1MA1) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.