[tex]\bf \cfrac{10!}{4!(10-4)!}\implies \cfrac{10!}{4!(6)!}\implies \cfrac{10\cdot 9\cdot 8\cdot 7\cdot \underline{6!}}{4!\underline{6!}}\implies \cfrac{10\cdot 9\cdot 8\cdot 7}{4!} \\\\\\ \cfrac{5040}{24}\implies 210[/tex]
