Question

mean of 15 observation is 23 if each is mulitiplied by 2 cm find new mean

Answer 1

mean = (x1+x2+x3------x15)/15

23  = (x1+x2+x3-----x15)/15

23*15  =  (x1+x2+x3------x15)

345 = x1+x2+x3----x15


it means that the sum of 23 observations is 345

if two multiplied in each 

then,

new mean = (2x1 + 2x2 ------2x15)/15

new mean =2(x1+x2-----x15)/15


it is given that the sum of the 15 observations is 345

now,    

new mean = 2(345)/15



new mean = 690/15

new mean = 46


i hope this will help you 



-by ABHAY