English

F 24cx = 24c2x + 3, Find X.

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Question

24Cx = 24C2x + 3, find x.

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Solution

Given:
 24Cx = 24C2x + 3
We have,

\[24 = x + 2x + 3\] [∵\[{}^n C_x = {}^n C_y \Rightarrow x = y\]]  or, \[n = x + y\]
\[\Rightarrow 24 = 3x + 3\]
\[ \Rightarrow 3x = 21\]
\[ \Rightarrow x = 7\]
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Chapter 17: Combinations - Exercise 17.1 [Page 8]

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R.D. Sharma Mathematics [English] Class 11
Chapter 17 Combinations
Exercise 17.1 | Q 5 | Page 8

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