Answer:
15
Step-by-step explanation:
n is the number of people and k the number of chairs
here n = 6 and k = 4
note n! = n(n - 1)(n - 2).... × 3 × 2 × 1, thus
[tex]\frac{6!}{4!(6 -4)!}[/tex]
= [tex]\frac{6(5)(4)(3)(2)(1)}{4!(2!)}[/tex]
= [tex]\frac{720}{4(3)(2)(1)2(1)}[/tex]
= [tex]\frac{720}{24(2)}[/tex]
= [tex]\frac{720}{48}[/tex]
= 15
