设鸡兔同笼,共有30个头,88只脚。求笼中鸡兔各有多少只?
方法一:
假设30个头全是兔,则脚的数量:30×4=120(只)
实际上脚有88只,比假设少:120-88=32(只)
一只鸡的脚比一只兔的脚少:4-2=2(只)
一只鸡比一只兔少2只脚,总计少了32只脚,则鸡的数量:32÷2=16(只)
兔的数量:30-16=14(只)
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/b90e7bec54e736d16935909e89504fc2d5626905?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
方法二:
假设30个头全是鸡,则脚的数量:30×2=60(只)
实际上脚有88只,比假设多:88-60=28(只)
一只兔的脚比一只鸡的脚多:4-2=2(只)
一只兔比一只鸡多2只脚,总计多了28只脚,则兔的数量:28÷2=14(只)
鸡的数量:30-14=16(只)
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/9922720e0cf3d7ca7dd023e0e01fbe096b63a905?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
方法三