Unit Week Funfair Additions 2 4 2 Count on 2 each time. 1 2 3 4 5 6 7 8 3 + 2 = 1 2 3 4 5 6 7 8 9 10 5 + 2 = 1 2 1 2 3 4 5 6 7 8 9 10 4 + 2 = 82