Let $\begin{aligned} \mathrm{A} &=\{\mathrm{x}: \mathrm{x}+4=4\}=\{\mathrm{x}: \mathrm{x}=4-4\} \\ &=\{\mathrm{x}: \mathrm{x}=0\}=\{0\} \end{aligned}$
Let the people who read all three papers $\mathrm{A}, \mathrm{B}, \mathrm{C}=\mathrm{x} \%$ So, people who read only A and $\mathrm{B}$ not $\mathrm{C}=(30-\mathrm{x}) \%$ People who read only $\mathrm{B}$ and $\mathrm{C}$, not $\mathrm{A}=(28-\mathrm{x}) \%$ People who read only A and $\mathrm{C}$, not $\mathrm{B}=(36-\mathrm{x}) \%$
Venn diagram representing these is shown below


Remaining numbers in circles are filled asshown below.
People who read only $\mathrm{A}+30-\mathrm{x}+\mathrm{x}+36-\mathrm{x}=42$
People reading only $\mathrm{A}=42-30-36+\mathrm{x}=(\mathrm{x}-24) \%$
Similarly, people who read only $\mathrm{B}=51-(30-\mathrm{x}+\mathrm{x}+28-\mathrm{x})$
$=51-(58-x)=51-58+x=(x-7) \%$
People who read only $\mathrm{C}=68-(36-\mathrm{x}+\mathrm{x}+28-\mathrm{x})$
$68-(64-x)=(x+4) \%$

Let $x \%$ people read all the three newspap
$8 \%$ people do not read any newspapers. $(x-24)+(x-7)+(x+4)+(30-x)+(36-x)+(28-x)+x=92$
$x+98-31=92$
$x=92-67=25$