The title is wrong, it should be: Three children weigh themselves, Xiaojie and Xiao Fei weigh 64 kg, Xiaohui and Xiao Fei weigh 60 kg, and Xiaojie and Xiaohui weigh 56 kg. Can you work out how many kilograms each of them weighs?
Solution: 64+60+56= 180
Three people did two calculations, so the total weight of three people is 180/2 = 90kg.
Xiaohui =90-64=26
Xiaojie =90-60=30
Xiao Fei =90-56=34