Question

The mean of 10 numbers is 15.2. If a new data whose value is 13 is introduced, new mean is

Answer 1

let sum of given 10 numbers is x
then given mean of 10 numbers is 15.2
so x/10 = 15.2
           x = 152
if 13 is added to the data
then new mean is x+13/11 = 152+13/11
                                              = 165/11
                                              = 15
the new mean of given data is 15