### The average weight of 12 crewmen in a boat is increased by $\Large\frac{1}{3}$ kg, when one of the crewmen whose weight is 55 kg is replaced by a new man. What is the weight of that new man ?

A. 58 kg B. 60 kg C. 57 kg D. 59 kg Answer: Option D
According to the question, Average weight of the 12 crewman increased by $=\frac{1}{3} \mathrm{~kg}$ \begin{aligned}&\text{∴ Total increase in weight}\\ &=12 \times \frac{1}{3} \\ &=4 \mathrm{~kg} \end{aligned} Weight of old man = 55 kg Weight of new man = 55 + 4 = 59 kg