Question

 (X + 1) + (X + 4) + (X +7) +(X + 10) + . . . + (X + 28) = 155

Answer 1

Answer 2

\(\left(x+1\right)+\left(x+4\right)+...+\left(x+28\right)=155\)

\(\Leftrightarrow10x=10\)

hay x=1

Answer 3

$\left(x+1\right)+\left(x+4\right)+\left(x+7\right)+\left(x+10\right)+....+\left(x+28\right)=155$

$\Rightarrow \left(x+x+x+....+x\right)+\left(1+4+7+10+...+28\right)=155$

$\Rightarrow 10x+145=155$

$\Rightarrow 10x=155-145$

$\Rightarrow 10x=10$

$\Rightarrow x=10:10$

$\Rightarrow x=1$

Answer 4