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Question
The median of observations 10, 11, 13, 17, x + 5, 20, 22, 24 and 53 (arranged in ascending order) is 18; find the value of x.
Solution
Total number of observations = 9(odd)
Now, if n = odd
Median = `(( n + 1)/2)^"th" "term"`
⇒ Median = `(( 9 + 1)/2)^"th" "term"` = 5th term = x + 5
Now, Median = 18 ...(given)
∴ x + 5 = 18
⇒ x = 13.
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