Question

The average weight of students in a class of $35$ students is $40kg.$ If the weight of the teacher is included, then the average rises by $\frac{1}{3}kg.$ The weight of the teacher is

• A. $40.5 \, kg$
• B. $50 \, kg$
• C. $41 \, kg$
• D. $52 \, kg$

Answer 1

Answer: (D)

Let, the weight of the teacher be $w$ $kg,$ then
$40+\frac{1}{3}=\frac{35 \times 40 + w}{35 + 1}$
$\Rightarrow 36\times 40+36\times \frac{1}{3}=35\times 40+w\Rightarrow w=52$
$\therefore $ Weight of the teacher $=52 \, kg.$