設(shè)x1,x2,x3,x4,x5,x6,x7是自然數(shù),且x1<x2<x3<x4<x5<x6<x7,x1+x2=x3,x2+x3=x4,x3+x4=x5,x4+x5=x6,x5+x6=x7,又x1+x2+x3+x4+x5+x6+x7=2010,
設(shè)x1,x2,x3,x4,x5,x6,x7是自然數(shù),且x1<x2<x3<x4<x5<x6<x7,x1+x2=x3,x2+x3=x4,x3+x4=x5,x4+x5=x6,x5+x6=x7,又x1+x2+x3+x4+x5+x6+x7=2010,那么x1+x2+x3的值最大是 ______.
優(yōu)質(zhì)解答
∵x
1+x
2+x
3+x
4+x
5+x
6+x
7=13x
1+20x
2=2010,
利用整除性,x
1必是10的奇數(shù)倍,又x
1<x
2,
可得
,,,(x
1+x
2+x
3)
max=2(x
1+x
2)
max=2(50+68)=236.
故答案為:236.
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