Question

The average weight of $40$ Students is $32$. If the Heaviest and Lightest are excluded the average weight reduces by $1$. If only the Heaviest is excluded then the average is $31$. Then what is the weight of the Lightest?

Answer 1

Average weight of $40$ students $=32$.

Total weight $=40\times 32=1280$.

Average weight of $38$ students except the heaviest and the lightest ones $=32-1=31$.

Total weight $=38\times 31=1178$.

Sum of weights of the heaviest and the lightest $=1280-1178=102$.

Average weight of $39$ students except the heaviest one $=31$.

Total weight $=39\times 31=1209$.

Weight of the heaviest $=1280-1209=71$

Weight of the lightest $=102-71=31$