1. Type in the two 2-digit values within your subtraction into the two boxes provided (Note: The top number has to be larger than the bottom number). An area representing the top number will be seen.[br]2. If the subtraction requires to borrow ten then a slider will appear for you to slide a ten across, causing an overlap of colour.[br]3. Use the subtract slider to separate the coloured area representing the lower number, leaving an area representing the result.