If 24Cx = 24C2x + 3, find x.

Asked by Sakshi | 1 year ago |  37

1 Answer

Solution :-

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

(i) p = q

(ii) n = p + q

So from the question 24Cx = 24C2x + 3, we can say that

Let us check for condition (i)

x = 2x + 3

2x – x = -3

x = -3

We know that for a combination nCr, r≥0, r should be a positive integer which is not satisfied here,

So, the condition (ii) must be satisfied,

24 = x + 2x + 3

3x = 21

x = \( \dfrac{21}{3}\)

x = 7

The value of x is 7.

Answered by Sakshi | 1 year ago

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