Subtraction Strip Board Incl Strips Tray

The board is identical to the addition strip board excepting that the vertical partition line is after the number 9. All the colours are just the opposite of the addition board. Wherever there is red, it is substituted with blue and vice versa. This set includes 2 strip trays. One is identical to the addition strip tray and the other contains seventeen grey strips the lengths of which correspond with the lengths of the number found on the top row.