i travelling to cambridge and am looking for a train to the london kings cross station leaving on thursday . i want to depart from cambridge after 19:45 and arrive at london kings cross .
where will you be traveling from on thursday ?
{'service': 'train', 'act': 'inform', 'slot_name': 'day', 'value': 'thursday'} {'service': 'train', 'act': 'inform', 'slot_name': 'leave', 'value': '21:00'} {'service': 'train', 'act': 'inform', 'slot_name': 'depart', 'value': 'cambridge'} {'service': 'train', 'act': 'inform', 'slot_name': 'dest', 'value': ' london kings cross'} {'service': 'train', 'act': 'inform', 'slot_name': 'id', 'value': 'tr0720'} {'service': 'train', 'act': 'request', 'slot_name': 'people', 'value': '?'}
tr0720 departs cambridge at 21:00 on thursday , heading to london kings cross . how many tickets do you need ?