<Table> Backgammon <Tr> <Td_colspan="2"> A backgammon set, consisting of a board, two sets of 15 checkers, two pairs of dice, a doubling cube, and dice cups </Td> </Tr> <Tr> <Th> Years active </Th> <Td> Approximately 5,000 years ago in Persia to present </Td> </Tr> <Tr> <Th> Genre (s) </Th> <Td> Board game Race game Dice game </Td> </Tr> <Tr> <Th> Players </Th> <Td> </Td> </Tr> <Tr> <Th> Setup time </Th> <Td> 10--30 seconds </Td> </Tr> <Tr> <Th> Playing time </Th> <Td> 5--60 minutes </Td> </Tr> <Tr> <Th> Random chance </Th> <Td> Medium (dice rolling) </Td> </Tr> <Tr> <Th> Skill (s) required </Th> <Td> Strategy, tactics, counting, probability </Td> </Tr> </Table> <Tr> <Td_colspan="2"> A backgammon set, consisting of a board, two sets of 15 checkers, two pairs of dice, a doubling cube, and dice cups </Td> </Tr>

How many dice are used in a standard game of backgammon