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Verified Answer :

are you asking 10 x C(5040) x 6??

Answer: A. 210

Step-by-step explanation:

We know that the number of combinations of n things taking r at time is given by expression :-

\(^nC_r=\dfrac{n!}{r!(n-r)!}\)  (1)

The given expression : \(^{10}C_{6}\) which basically gives the number of combinations of 10 things taking 6 at a time.

Using (1) , we have

\(^{10}C_{6}=\dfrac{10!}{6!(10-6)!}\\\\=\dfrac{10\times9\times8\times7\times6!}{6!4!}\\\\=\dfrac{10\times9\times8\times7}{4!}\ \ [\text{Cancel }6!\text{ from numerator and denominator}]\\\\=\dfrac{10\times9\times8\times7}{4\times3\times2\times1}\\\\=210\)

Hence, the correct answer is A. 210 .