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If the Arithmetic Mean, 7, 8, X, 11, 14 is X, Then X = - Mathematics

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Question

If the arithmetic mean, 7, 8, x, 11, 14 is x, then x =

Options

  • 9

  • 9.5

  • 10

  • 10.5

MCQ

Solution

The given observations are 7, 8, x, 11, 14.
Mean = x       (Given)
Now,

\[\text { Mean } = \frac{7 + 8 + x + 11 + 14}{5}\] 
 
\[ \Rightarrow x = \frac{40 + x}{5}\] 
 
\[ \Rightarrow 5x = 40 + x\] 
 
\[ \Rightarrow 4x = 40\] 
 
\[ \Rightarrow x = 10\]
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Chapter 15: Statistics - Exercise 15.8 [Page 68]

APPEARS IN

RD Sharma Mathematics [English] Class 10
Chapter 15 Statistics
Exercise 15.8 | Q 29 | Page 68

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