Question

Tìm x :

( x+2)+(x+4)+(X+6)+............+(x+100)=2700

Answer 1

=> ( x + x + x + .... + x + x ) + ( 2 + 4 + 6 + .... + 98 + 100 ) = 2700

=> 50x + { [ ( 100 - 1 ).50 ] : 2 } = 2700

=> 50x + 2550 = 2700

=> 50x = 2700 - 2550 = 150

=> x = 150 : 50 = 3

Vậy x = 3

Answer 2

tham khao bai cua minh nhe

x+x+...+x+2+4+6+...+100=2700

Dat A=2+4+6+...+100

      so so hang cua A la (100-2):2+1=50

      Tong A la :(100+2). 50:2=2550

  =>x.50+2550=2700

  =>x=150:50=30