[tex] \frac{m}{123} = \frac{n}{492} [/tex]
[tex] \frac{4m}{492} = \frac{n}{492} [/tex]
[tex]4m \times 492 = 492n[/tex]
[tex]4m = n[/tex]
[tex]m \times n = 324[/tex]
[tex]m \times 4m = 324[/tex]
[tex] {m}^{2} = 324 \div 4[/tex]
[tex] {m}^{2} = 81[/tex]
[tex]m = \sqrt{81} = 9[/tex]
[tex]n = 4m = 4 \times 9 = 36[/tex]
