Q9 of 71 Page 199

The mean of 13 numbers is 24. If 3 is added to every number, what will be new mean?

We know that,


Where, = Mean, xi = observations and n = no. of observations.


Let the sum of 13 numbers be S.



⇒ S = 312


Now, let new mean be ̅y.




⇒ = 27


⇒ new mean = 27.


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