Question

27. Resolva a equação: C10,2 + C10,3 = C11,x.

Answer 1

C10,2+C10,3=C11,x
10!/2!8!+10!/3!7!=11!/x!(11-x)!
45+120=11!/x!(11-x)!
165(x!(11-x)!)=11!
x!(11-x)!=241920
x!(11-x)!=2^8.3³.5.7
x=8

$\boxed{ \boxed{ \boxed{ \mathsf{x = 8}}}}$