Chapter 12 - Sequences; Induction; the Binomial Theorem - 12.5 The Binomial Theorem - 12.5 Assess Your Understanding - Page 836: 14

$4,191,844,505,805,495$

Recall: ${n\choose j}=\dfrac{n!}{(n-j)!j!}$. Hence, using the formula above and acalculator gives''\begin{align*} \require{cancel} {60\choose 20}&=\dfrac{60!}{(60-20)!20!}\\ &=\dfrac{60!}{40!20!}\\ &=4,191,844,505,805,495\end{align*}