If ^n C_ 12 = ,^n C_6 , then ^n C_2 = - Vidyadip

MCQ

If $^n{C_{12}} = {\,^n}{C_6}$, then $^n{C_2} = $

A
$72$
✓
$153$
C
$306$
D
$2556$

✓

Answer

Correct option: B.

$153$

b
(b) Given ${\,^n}{C_{12}} = {\,^n}{C_6}$

$12 + 6 = n \Rightarrow n = 18$

$^{18}{C_2} = \frac{{18 \times 17}}{2} = 9 \times 17 = 153$.

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