A method including, manufacturing individual playing cards; shuffling, using a shuffling machine with multiple pockets, a multiple number of decks of the playing cards at random in a factory utilizing at least a first card feeding step and a second card feeding step; detecting, using an imaging device and an image processing unit, a rank and a suit of each of the cards; counting, using the image processing unit, the number of each rank and each suit; inspecting, using the image processing unit, during or after the shuffling of the decks of playing cards, but before packaging, whether or not there is an excess or deficiency in the number of the rank or the suit contained in the multiple number of decks of the playing cards; and, after the inspecting step, packaging a set of the shuffled decks of the playing cards in an individual package.