[tex]\displaystyle\bf\\Numarul~de~microstari~al~sistemului~este:\\\\n=C_{10}^3\\\\n=\frac{A_{10}^3}{P_3}\\\\n=\frac{10\times9\times8}{1\times2\times3}\\\\n=10\times3\times4\\\\n=10\times(3\times4)\\\\n=10\times12\\\\\boxed{\bf n=120~microstari}[/tex]
