有一列数:1,2,3,2,1,2,3,4,3,2,3,4,5,4,3,4,5,6,5,4,5,.这列数中前240个数的和是()谢谢!求算式!

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有一列数:1,2,3,2,1,2,3,4,3,2,3,4,5,4,3,4,5,6,5,4,5,.这列数中前240个数的和是()谢谢!求算式!

有一列数:1,2,3,2,1,2,3,4,3,2,3,4,5,4,3,4,5,6,5,4,5,.这列数中前240个数的和是()谢谢!求算式!
有一列数:1,2,3,2,1,2,3,4,3,2,3,4,5,4,3,4,5,6,5,4,5,.这列数中前240个数的和是()谢谢!求算式!

有一列数:1,2,3,2,1,2,3,4,3,2,3,4,5,4,3,4,5,6,5,4,5,.这列数中前240个数的和是()谢谢!求算式!
五个一组,和为等差数列
第一组和为9
最后一组,和为244
共48组,
和为
(9+244)×48÷2
=253×24
=6072

667

很高兴为你作答 五个一循环一共48项第一项为9最后一项为244则可(244+9)乘48除2得6072

6072

每5个为1组,每组和分别为9,14,19,24,......56。
共240/5=48组
(9+56)X48÷2=65X24
=1560