Answer
$4,950$
Work Step by Step
RECALL:
${n}\choose{k}$$=\dfrac{n!}{k!(n-k)!}$
Use the formula above to obtain:
${100}\choose{98}$$\require{cancel}
\\=\dfrac{100!}{98!(100-98)!}
\\=\dfrac{100!}{98!2!}
\\=\dfrac{100\cdot 99 \cdot 98!}{98! (2\cdot 1)}
\\=\dfrac{\cancel{100}^{50}\cdot 99 \cdot \cancel{98!}}{\cancel{98!} (\cancel{2}\cdot 1)}
\\=4950$
