Question

The average weight of students in a class of $32\,$ students is $40\,kg$ . If the weight of the teacher be included, the average rises by $\frac{1}{3}\,kg$ , then the weight of the teacher is

• A. $40.5 \, kg$
• B. $50 \, kg$
• C. $41 \, kg$
• D. $51 \, kg$

Answer 1

Answer: (D)

Let, the weight of the teacher be $wkg$ , then
$40+\frac{1}{3}=\frac{32 \times 40 + w}{32 + 1}$
$\Rightarrow 33\times 40+33\times \frac{1}{3}=32\times 40+w\Rightarrow w=51\,$
$\therefore $ Weight of the teacher $=51\,kg$