Respuesta :

[tex]\begin{gathered} \text{Prime Factor of }140 \\ \\ 140=2\times2\times5\times7 \end{gathered}[/tex]

By listing the multiples of 84 and 140, we have

Multiples of 84 → 84, 168, 252, 336, 420, 504

Multiples of 140 → 140, 280, 420, 560

Therefore, the LCM of 84 and 140 is 420.