Question 1169590


use combination formula:

{{{nCr=n!/((n-r)!r!)}}} where {{{n=9}}} and {{{r=7}}}


{{{9C7=9!/((9-7)!7!)}}}


{{{9C7=9!/(2!7!)}}}


{{{9C7=(9*8*7*6*5*4*3*2*1)/((2*1)(7*6*5*4*3*2*1))}}}...simplify


{{{9C7=(9*cross(8)4*cross(7*6*5*4*3*2*1))/((cross(2*1))cross((7*6*5*4*3*2*1)))}}}


{{{9C7=9*4}}}


{{{9C7= 36}}}

{{{36}}} website graphics can be created by using at least seven of nine different bitmap images