as far as I'm aware solutions to the two question 4s are:
decimal steps (i) Q4 : has two solutions (maybe more)
- A = + 0.2 , B = x 3 , C = x 2
- A = + 0.6 , B = x 3 , C = + 1
these two questions are difficult but some groups of 11 year olds have obtained solutions...