Question

The average $50$ numbers is $30$. If two numbers, $35$ and $40$ are discarded, then the average of the remaining numbers is nearly:

• A. $28.32$
• B. $28.78$
• C. $29.27$
• D. $29.68$

Answer 1

The correct option is D $29.68$

Given

$30=\frac{a_1+a_2+a_3+---+a_{49}+a_{50}}{50}$

$\Rightarrow a_{49}+a_{50}=1500-(a_1+a_2+---+a_{48})$

Now, $a_{49}$ & $a_{50}$ is removed

$Savg=\frac{a_1+a_2+---+a_{48}}{48}$

$=\frac{1500-(35+40)}{48}$

$=\frac{1500-75}{48}$

$=\frac{1425}{48}$

$Savg=29.68$