question_answer

The average of n numbers\[{{x}_{1}},{{x}_{2}},{{x}_{3}},.....,{{x}_{n}}\]is A.  If \[{{x}_{1}}\]is replaced by\[(x+a){{x}_{1}},{{x}_{2}}\]is replaced by \[(x+a){{x}_{2}},.....,\]then the new average is______.

A) \[(x+a)A\]                     

B) \[\frac{(x-1)A+n{{x}_{n}}}{n}\]

C)                    \[\frac{nA+(n+1){{x}_{n}}}{n}\]         

D)        \[\frac{(n+1)A+{{x}_{n}}}{n}\]                       

Correct Answer: A

Solution :

It is given that, Now, each number is multiplied by New mean