\(5xyz.15{x^3}{y^2}z \)\(\,= \left( {5.15} \right){\rm{.}}\left( {x.{x^3}} \right){\rm{.}}\left( {y.{y^2}} \right){\rm{.}}\left( {z.z} \right){\rm{ }} \)\(\,= 75{x^4}{y^3}{z^2}\)
\(5xyz.25{x^4}yz \)\(\,= \left( {5.25} \right).\left( {x.{x^4}} \right).\left( {y.y} \right).\left( {z.z} \right) \)\(\,= 125{x^5}{y^2}{z^2}\)
\(5xyz.\left( { - {x^2}yz} \right) \)\(\,= \left[ {5.\left( { - 1} \right)} \right].\left( {x.{x^2}} \right).\left( {y.y} \right).\left( {z.z} \right) \)\(\,= - 5{x^3}{y^2}{z^2}\)
\(5xyz.\left( { - \dfrac{1}{2}x{y^3}z} \right) \)\(\,= \left[ {5.\left( { - \dfrac{1}{2}} \right)} \right].\left( {x.x} \right).\left( {y.{y^3}} \right).\left( {z.z} \right) \)\(\,= - \dfrac{5}{2}{x^2}{y^4}{z^2}\)
