Answer:
10
Step-by-step explanation:
n is the number of selections and k the number selected, that is
n = 5 and k = 2
note that n! = n(n - 1)(n - 2) ..... × 3 × 2 × 1, thus
[tex]\frac{5(4)(3)(2)(1)}{2!(5-2)!}[/tex]
= [tex]\frac{120}{2(1)3(2)(1)}[/tex]
= [tex]\frac{120}{2(6)}[/tex]
= [tex]\frac{120}{12}[/tex]
= 10
