\(\dfrac{158-x}{31}+\dfrac{185-x}{29}+\dfrac{208-x}{27}+\dfrac{227-x}{25}=10\\ < =>\dfrac{158-x}{31}+\dfrac{185-x}{29}+\dfrac{208-x}{27}+\dfrac{227-x}{25}-10=0\\ < =>\dfrac{158-x}{31}-1+\dfrac{185-x}{29}-2+\dfrac{208-x}{27}-3+\dfrac{227-x}{25}-4=0\)
\(< =>\dfrac{127-x}{31}+\dfrac{127-x}{29}+\dfrac{127-x}{27}+\dfrac{127-x}{25}=0\)
\(< =>\left(127-x\right)\left(\dfrac{1}{31}+\dfrac{1}{29}+\dfrac{1}{27}+\dfrac{1}{25}\right)=0\\ < =>127-x=0\left(\dfrac{1}{31}+\dfrac{1}{29}+\dfrac{1}{27}+\dfrac{1}{25}\ne0\right)\\ < =>x=127\)
=>\(\left(\dfrac{158-x}{31}-1\right)+\left(\dfrac{185-x}{29}-2\right)+\left(\dfrac{208-x}{27}-3\right)+\left(\dfrac{227-x}{25}-4\right)=0\)
=>127-x=0
=>x=127
