Question

A number is multiplied by 3 and increased by 5 is equal to the same number multiplied by 7 and decreased by 15. Find the number.

Answer 1

$$\begin{gathered} \mathrm{Hi}, \\ \mathrm{Let}\mathrm{the}\mathrm{number}\mathrm{is}\mathrm{x}\mathrm{so} \\ 3\mathrm{x}+5=7\mathrm{x}-15 \\ 7\mathrm{x}-3\mathrm{x}=5+15 \\ 4\mathrm{x}=20 \\ \mathrm{x}=5 \\ \mathrm{so}\mathrm{the}\mathrm{number}\mathrm{is}5 \end{gathered}$$