Question

what is the common factor of 49 and 63

Answer 1

$$\begin{gathered} \mathrm{Factors}\mathrm{of}49\mathrm{are}1,7,49 \\ \mathrm{Factors}\mathrm{of}63\mathrm{are}1,3,7,9,21,63 \\ \mathrm{Hence}\mathrm{the}\mathrm{common}\mathrm{factors}\mathrm{of}49\mathrm{and}63\mathrm{are}1\mathrm{and}7. \end{gathered}$$