3+6+9+12+·······+198+201的和是多少

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3+6+9+12+·······+198+201的和是多少

3+6+9+12+·······+198+201的和是多少
3+6+9+12+·······+198+201的和是多少

3+6+9+12+·······+198+201的和是多少
=3*(1+2+3+4+……+67)
=3*(1+67)*67/2
=6834

6834

6834

3+6+9+12+。。。+198+201=3(1+2+3+4+。。。+66+67)=6834

6834
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这就和那个高什么定律一样1+2+3+4+5+……+95+96+97+98+99

6834

(201-3)/2*(201+3)+69

等于3*(1+2+3+4.。。。。+66+67)=3*(1+67)*67/2=6834

33*204+102=6834

3(1+2+3+...+67)=3(67+1)67/2=3*34*67=6834

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