(x+1)+(x+2)+...+(x+100) = 5750
(x+x+x+.....+x) + ( 1+2+..+100) = 5750
100x + 5050 = 5750
100x = 5750 - 5050
100x = 700
x = 700 : 100
x = 7
100 . x + ( 1 + 2 + 3 + ....+ 100 )
100 . x + 100 . 101 : 2
=> 100x + 101 + 50 = 5750
100x = 5750 - 5050 = 700
=> x = 700 : 100=7
=> x = 7
(x+1)+(x+2)+(x+3)+...+(x+100)=5750
100x + ( 1 + 2 + 3 + ... + 100 ) = 5750
100x + 101 . 100 : 2 = 5750
100x + 5050 = 5750
100x = 700
x = 7