Question

tính

x+(x+1)+(x+2)+...+(x+100)=210

Answer 1

x+(x+1)+(x+2)+...+(x+100) = 210

=> 101x + 100 x (100 + 1) :2 = 210

=> 101x + 5050 = 210

=> 101x = 210 - 5050

=> 101x = -4840

=> x = -4840 : 101

=> x = -4840/101

Answer 2

 

tính

x+(x+1)+(x+2)+...+(x+100)=210

(100x) + ( 1+2+...+100 ) = 210

 (100x)   + 5050 = 210

   100x    = 210 - 5050 = -4840

         x = -4840 : 100

            x = -48,4