Question

The mean of $50$ observations is $36$. If two observations $30$ and $42$ are deleted, then the mean of the remaining observations is

• A. $36$
• B. $48$
• C. $38$
• D. None of these

Answer 1

The correct option is A $36$

Let $u=36$ be the mean of $50$ observations.
$\therefore u\times 50=x_1+x_2.....+x_{50}$
Now two observations $30$ and $42$ are deleted.
So, sum of remaining observations$=50\times 36-42-30=1728$
$\therefore u^{\prime }=\frac{1728}{48}=36$
Ans- Option A.