Answer:
A. 1287
Step-by-step explanation:
nCr= n!/[(n-r)!(r!)]
13C5= 13!/[(13-5)!(5!)]
13C5=13!/[(8)!(5!)]
13C5=13!/[(8!)(5!)]
13C5=[(13)(12)(11)(10)(9)(8!)]/[(8!)(5!)]
Cross out both 8! which leaves you to,
13C5=[(13)(12)(11)(10)(9)]/[5!]
13C5=[(13)(12)(11)(10)(9)]/[(5)(4)(3)(2)(1)]
13C5=154440/120
13C5=1287
