内容正文:
第七讲 找规律填数
【例题2】找出前面几个数的排列规律,并填出括号里的数。
① 2,3,4,5,6,( ),( )
② 9,8,7,6,( ),( )
③ 1,3,5,7,9,( ),( )
④ 2,4,6,8,( ),( )
⑤ 2,5,8,11,( ),( )
⑥ 16,13,10,7,( ),( )
⑦ 6,9,12,15,( ),( )
⑧ 20,18,16,14,( ),( )
【例题2】先找出规律,然后在( )里添上合适的数。
① 15,3,13,3,11,3,,( ),( )
② 1,4,2,5,3,6,( ),( )
③ 1,10,2,9,3,8,4,7,( ),( )
④ 8,15,10,13,12,11,( ),( )
⑤ 3,5,3,10,3,15,3,20,( ),( )
⑥ 15,1,20,2,25,3,( ),( )
⑦ 1,6,2,12,3,18,( ),( )
⑧ 5,5,5,5,5,( ),( )
【例题3】找出前面几个数的排列规律,并填出括号里的数。
① 1,2,4,5,7,8,10,( ),( )
② 2, 4, 7, 9, 12, 14, 17,( ),( )
③ 1, 2, 4, 7, 11, 16, 22,( ),( )
④ 3, 6, 10, 15, 21, 28, ( ),( )
+-×÷ 我能行 +-×÷
练习1根据规律填数
(1)30,28,26,( ),( ),( );
(2)1,3,6,( ),( );
(3)15,20,25,( ),( ),( ).
练习2 根据规律填空
(1) ⑦ ⑨ 〇 〇
③ ④ ④ ⑤ ⑤ 〇 〇 ⑦
(2) ① ③ ④