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Question
If the mean of 5 observation x, x + 2, x + 4, x + 6and x + 8 , find the value of x.
Solution
Mean of given observations =` "sun of given observations"/"total number of observations"`
∴ 11 =`(x + (x+2)+(x+4)+(x+6)+(x+8))/5`
⇒ 55 = 5x + 20
⇒ 5x = 55 – 20
⇒ 5x = 35
⇒ x =`35/5`
⇒ x = 7
Hence, the value of x is 7.
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