Question 749043


{{{nPr=n!/(n-r)!}}}

{{{4P2=4!/(4-2)!}}}

{{{4P2=4!/2!}}}

{{{4P2=(4*3*2*1)/(2*1)}}}

{{{4P2=(4*3*cross(2*1))/cross((2*1))}}}

{{{4P2=4*3}}}

{{{4P2=12}}}