This demonstration has used multiple sets of cards in order to display a method of subtraction. Larger cards would require an inconveniently larger space
The size chosen for Dart Number and Symbol cards follows the advice of parents and experienced teachers. Many of the uses we suggest ~ and envisage users to be devising ~ involve laying cards down onto a table. Normal playing cards can take up too much room for convenience.
Both adults and children find the technique of holding and displaying cards in the hand difficult at first. This ~ we believe ~ is not a function of the size of the card. It has to do with the experience of fingers-and-cards manipulation.
The manufacturer's size is called 'Patience' which is a resonable descriptor, based on the miniature frequently used in years gone by. Checking on Wikipedia I see that there is a huge range of 'Patience' card sizes. In round term Dart Cards are much the same as one half of a normal playing cards 32x62 (1+26/32)" by (2+1/2)"
