Question

(x+1)+(x+2)+......+(x+100) = 5750

m.n ơi làm hộ mình nha cảm ơn mọi  người nhìu nhìu

 

Answer 1

(x+1)+(x+2)+(x+3)+...+(x+100)

=(x+x+...)+(1+2+3+4+...+100)

=x.100+(1+100x100:2)

=x.100+5050=5750

x.100=5750-5050

x.100=700

x=700:100

vậy x=7

Answer 2

( x + 1 ) + ( x + 2 ) + ... + ( x + 100 ) = 5750

<=>( x + x + ... + x ) + (  1 + 2 + ... + 100 ) = 5750

          100 số x

<=>   x.100 + ( 100 + 1 ) .100 : 2 = 5750

<=>   x . 100 + 5050 = 5750

=> x . 100 = 700

=> x = 7

Answer 3

(x + 1) + (x + 2) + ...... + (x + 100) = 5750

(x + x + ... + x) + (1 + 2 + 3 + 4 + 5 + ... + 100) = 5750

            x . 100 + (1 + 2 + 3 + 4 + 5 + ... + 100) = 5750

                           x . 100 + ([100 + 1) . 100 : 2) = 5750

                                                x . 100 + 5050 = 5750

                                                           x . 100 = 5750 - 5050

                                                           x . 100 = 700

                                                                    x = 700 : 100 = 7