Question

if the mean of a set of observations x1,x2,x3......x10 is 25.find the mean of x1+3,x2+6,x3+9......x30+30 is

Answer 1

Answer:

41.5

Step-by-step explanation:

Given  

if the mean of a set of observations x1,x2,x3......x10 is 25.find the mean of x1+3,x2+6,x3+9......x30+30 is

Now n = 10 and mean = 25

So mean = x1 + x2 + x3 + ---------+xn / n

       25 = x1 + x2 + x 3+-----------+ x 10 / 10

Now x1 + x2 +----------+ x 10 = 250

Also x1 + 3, x2 + 6 x3 + 9----------xn + 30

Now mean = x1 + 3 + x2 + 6+------+x10 + 30 / 10

Mean = (x1 + x2 +-----+ x10) + (3 + 6 + 9 +------30)

Mean = 250 + 165 / 10  

         = 415 / 10

Hence Mean = 41.5