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If nC12 = nC5, find the value of n. - Mathematics

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Question

If nC12 = nC5, find the value of n.

Sum
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Solution

We have,

nC12 = nC5

(i) p = q

(ii) n = p + q

Therefore, from the question nC12 = nC5, we can say that

12 ≠ 5

Therefore, the condition (ii) must be satisfied,

n = 12 + 5 

n = 17

∴ The value of n is 17.
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Chapter 17: Combinations - Exercise 17.1 [Page 8]

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RD Sharma Mathematics [English] Class 11
Chapter 17 Combinations
Exercise 17.1 | Q 2 | Page 8

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