Question 1169645
 

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

{{{7P4=7!/(7-4)!}}}

{{{7P4=7!/3!}}}

{{{7P4=(7*6*5*4*3*2*1)/(3*2*1)}}}

{{{7P4=(7*6*5*4*cross(3*2*1))/(cross(3*2*1))}}}

{{{7P4=7*6*5*4}}}

{{{7P4=840}}}




{{{nCr=n!/((n-r)!*r!)}}}

{{{7C4=7!/((7-4)!*4!)}}}

{{{7C4=7!/(3!*4!)}}}

{{{7C4=(7*6*5*4*3*2*1)/((3*2*1)*(4*3*2*1))}}}

{{{7C4=(7*cross(6)*5*cross(4*3*2*1))/((cross(3*2*1))*cross((4*3*2*1)))}}}

{{{7C4=7*5}}}

{{{7C4=35}}}