B) 58
C) 59
D) 60
Let the average weight of the 59 students be X. Therefore, the total weight of the 59 of them will be 59X.
The question states that when the weight of this student who left is added, the total weight of the class = 59X + 45.
When this student is also included, the average weight decreases by 0.2 kgs.
59X + 45/ 60 = X – 0.2
=> 59X + 45 = 60X – 12
=> 45 + 12 = 60X – 59A
=> X = 57.
Related MCQs:
- There are two sections A and B of a class, consisting of 36 and 44 students respectively. If the average weight of section A is 40kg and that of section B is 35kg, find the average weight of the whole class.
- In a class 3/4th of the students do not know either English or Hindi. But 1/6th of the students know English. How many students know both English and Hindi if students who know Hindi are 1/8th of total students in the class?
- There are two sections A and B of a class, consisting of 36 and 44 students respectively. If the average weight of section A is 40kg and that of section B is 35kg, find the average weight of the whole class?
- 3 boxes have some average weight .when one box which weight 89kg is replaced by another box ,the average weight increases by 5kg .how much the new box weight?