考點:數(shù)列中的規(guī)律
專題:探索數(shù)的規(guī)律
分析:(1)0.6-0.1=0.5,1.1-0.6=0.5,1.6=1.1=0.5,后一個數(shù)比前一個數(shù)多0.5;
(2)這個數(shù)列的奇數(shù)項是1.8,1.6,后一個數(shù)奇數(shù)項的數(shù)比前一個奇數(shù)項數(shù)少0.2;
偶數(shù)項的數(shù)是:0.2,0.4后一個數(shù)偶數(shù)項的數(shù)是前一個偶數(shù)項數(shù)的2倍,由此求解.
解答:
解:(1)1.6+0.5=2.1,
2.1+0.5=2.6,
2.6+0.5=3.1,
3.1+0.5=3.6;
(2)要求的第一個數(shù)和第三個數(shù)都是奇數(shù)項的數(shù),它們分別是:
1.6-0.2=1.4,
1.4-0.2=1.2;
要求的第二個數(shù)和第四個數(shù)都是偶數(shù)項的數(shù),它們分別是:
0.4×2=0.8,
0.8×2=1.6;
故答案為:1.4,0.8,1.2,1.6.
點評:解決本題先找出規(guī)律,再根據(jù)規(guī)律進行求解即可.