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If 18cx = 18cx + 2, Find X. - Mathematics

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Question

If 18Cx = 18Cx + 2, find x.

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Solution

Given: 
18Cx = 18Cx + 2

By using

\[{}^n C_x = {}^n C_y \Rightarrow x = y\] or \[n = x + y\]
 we get,
\[18 = x + x + 2\]
\[ \Rightarrow 2x = 16\]
\[ \Rightarrow x = 8\]
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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 6 | Page 8

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