鸡兔同笼,有12个头,40只脚,算一算,笼子里有几只鸡,几只兔?

问题描述:

鸡兔同笼,有12个头,40只脚,算一算,笼子里有几只鸡,几只兔?

兔有:
(40-12×2)÷(4-2),
=16÷2,
=8(只);
鸡有:12-8=4(只);
答:鸡有4只,兔有8只.