JEE Main & Advanced Mathematics Statistics Question Bank Self Evaluation Test - Statistics

  • question_answer
    If the arithmetic mean of the numbers \[{{x}_{1}},{{x}_{2}},{{x}_{3}},...{{x}_{n}}\] is \[\bar{x}\]. Then the arithmetic mean of numbers \[a{{x}_{1}}+b,a{{x}_{2}}+b,a{{x}_{3}}+b,...a{{x}_{n}}+b,\] Where a, b are two constants would be

    A) \[\bar{x}\]

    B) \[na\bar{x}+nb\]

    C) \[a\bar{x}\]

    D) \[a\bar{x}+b\]

    Correct Answer: D

    Solution :

    [d] Required mean \[=\frac{(a{{x}_{1}}+b)+(a{{x}_{2}}+b)+...+(a{{x}_{n}}+b)}{n}\] \[=\frac{a({{x}_{1}}+{{x}_{2}}+...+{{x}_{n}})+nb}{n}=a\bar{x}+b,\] \[\left( \because \frac{{{x}_{1}}+{{x}_{2}}+...+{{x}_{n}}}{n}=\bar{x} \right).\]


You need to login to perform this action.
You will be redirected in 3 sec spinner