Let the observations be x1,x2,...,x50.
Given (x1−30)+(x2−30)+.....+(x50−30)=50
⇒x1+x2+.....+x50=50+(30×50)=1550
Now, Mean =50x1+x2+....+x50=501550=31.
If the sum of the deviations of 50 observations from 30 is 50, then the mean of these observations is :
Held on 12 Jan 2019 · Verified 6 Jul 2026.
30
51
50
31
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