The average weight of a group of 22students is 34kg. When the weight of the staff is also included, the average weight increases by 2kg. What is the weight of the staff? A. 80 kgs B. 54 kgs C. 47 kgs D. 33kgs
A)
The average weight of a group of 22students = 34 kgs.
Therefore, the total weight of the group = 22*34 = 748 kg
When the weight of the staff is included, there are 23 individuals.
The average weight increases by 2kg. That is the new average weight = 36 kgs.
Therefore, the total weight of the 22 students plus the staff = 23* 36= 828
828-748=80 kg.