Q. 65.0( 1 Vote )

# If ^{18}C_{x} = ^{18}C_{x + 2}, find x.

Answer :

We know that if , then one of the following conditions need to be satisfied:

i. p = q

ii. n = p + q

From the problem we can say that,

⇒ x≠x + 2

So, the condition(ii) must be satisfied,

⇒ 18 = x + x + 2

⇒ 2x = 16

⇒

⇒ x = 8.

∴ The value of x is 8.

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