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1+2+3+...+29+30+35+500 urgenttt


Răspuns :

1000

S=1+2+3+...+30
S=30+29+28+...+1
2S=31+31+31+...+31(de 30 de ori)
2S=31x30=930
S=930:2=465

465+35+500= 1000