数列2,5,11,20,X,47中则X=?
来源:百度知道 编辑:UC知道 时间:2024/05/28 16:28:59
数列2,5,11,20,X,47中则X=?
步骤
步骤
32
5 - 2 = 3 = 1*3
11 - 5 = 6 = 2*3
20 - 11 = 9 = 3*3
32 - 20 = 12 = 4*3
47 - 32 = 15 = 5*3
x=32
5-2=1*3
11-5=6=2*3
20-11=9=3*3
32-20=12=4*3
47-32=15=5*3
2+3=5
5+3*2=11
11+3*3=20
20+3*4=32
32+3*5=47
x=32
5=2+3
11=2+3+6
20=2+3+6+9
X=2+3+6+9+12
47=2+3+6+9+12+15
所以
X=2+3+6+9+12=32
2,5,11,20,32,47
X=32
他们的规律是依次递增3,6,9,12,15.......每次+3
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