找规律填数字21.18.16.13.11( )

2025-07-25 02:10:12
推荐回答(1个)
回答1:

其实这题的规律是相邻两项的和是等差数列
21+18=39
18+16=34
16+13=29
13+11=24
11+()=24-5
()=8