The 1983 Summer Universiade, also known as the 1983 World University Games or XII Summer Universiade, took place in Edmonton, Alberta, Canada between July 1 and 12, 1983. Over 2400 athletes from 73 countries participated. It was the first time Canada hosted these Games. Edmonton also hosted the 1978 Commonwealth Games.
The 1983 Summer Universiade took place in Edmonton, Alberta, with athletes from more than 2400 different countries participating. 
The context states that over 2400 athletes participated but they only came from 73 different countries. The system probably was confused because the statement and the context both mention the number 2,400. 