Question

In a class with a certain number of students if one student weighing 50 kg is added then the average weight of the class increases by 1 kg. if one more student weighing 50 kg is added then the average weight of the class increases by 1.5 kg over the original average. what is the original average weight (in kg) of the class?

Answer 1

The options for this question are missing here are the options:

A) 46

B) 4

C) 2

D) 47

Answer

Let number of students in the class be n

Average weight of the class be x

Total weight of the class = nx

If one student (50 kg) joins, comparing total weight of the class

(n+1)(x+1) = nx + 50

If second student (50 kg) joins, comparing total weight of the class

(n+2)(x+1.5) = nx + 100

Solving the equations we get

n + x = 49 - (1)

1.5n + 2x = 97 - (2)

From (1), n = 49 - x

Putting in (2) we get

73.5 + 0.5 x = 97  

0.5x = 23.5 or x = 47

Answer 2

Answer:

more step this ans. is. o