Question

I have a data set of 25, 28, 36, 21, 28, 15, 24, 30. if a number is added to the set the mean becomes 27, what is the number???

Answer 1

Mean = Sum of points / Number of points ;

27 = ( 25 + 28 + 36 + 21 + 28 + 15 + 24 + 30 + x ) / 9 ;

243 = 207 + x ;
x = 36 is the number ;