11加12+13家14+15+6+7+18+19+20+...39+40等于多少

11加12+13家14+15+6+7+18+19+20+...39+40等于多少
2025-06-22 05:17:09
推荐回答(3个)
回答1:

等差数列

回答2:

=(11+40)×15
=51×15
=765

回答3:

=51×15=765