1,4,3,5,2,6,4,7,() a.4 b.3 c.1 d.2 弄不懂啊

问题描述:

1,4,3,5,2,6,4,7,() a.4 b.3 c.1 d.2 弄不懂啊

答案:B=3 .第一数+第三数=第二数,同里:3数+5数=4数.5数+7数=6数→4+N=7→N=3