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# The average weight of 25 boys was calculated to be 78.4 kg. It was later discovered that one weight was misread as 69 kg instead of 96 kg. The correct average is

$\begin {array} {1 1} (A)\;79\: kg & \quad (B)\;79.48\: kg \\ (C)\;81.32\: kg & \quad (D)\;None \: of \: these \end {array}$

Incorrect sum of all items = $78.4 \times 25$
$= 1960 kg$
$\therefore$ Correct sum = $1960-69+96$
$= 1987 kg$
$\therefore$ correct average = $\large\frac{1987}{25}$
$= 79.48 kg$

+1 vote