Question

Find a number such that four-fifths of the number is 4less than 8

Answer 1

$$\begin{gathered} \mathrm{Let}\mathrm{the}\mathrm{required}\mathrm{number}=x \\ \mathrm{Now},\mathrm{according}\mathrm{to}\mathrm{question}, \\ \frac{4}{5}\mathrm{of}\mathrm{the}\mathrm{number}=4\mathrm{less}\mathrm{than}8 \\ \Rightarrow \frac{4}{5}x=8-4 \\ \Rightarrow \frac{4x}{5}=4 \\ \Rightarrow 4x=20 \\ \Rightarrow x=\frac{20}{4}=5 \\ \mathrm{Hence}\mathrm{the}\mathrm{required}\mathrm{number}=x=5 \end{gathered}$$