The average weight of a class of 39 students is 40kg When a new student is admitted to the class the...

Question

The average weight of a class of 39 students is 40kg When a new student is admitted to the class the average decreases by 200g Find the weight of the new student

Accepted Answer

It is given that

Mean weight of 39 students = 40kg

So the total weight = 40 (39) = 1560kg

It is given that when a new student is admitted to the class, the average decreases by 200g

So the new mean = 40 – 0.2 = 39.8kg

We know that

Total weight of 40 students = 39.8 (40) = 1592kg

So the weight of new student = total weight of 40 students – total weight of 39 students

By substituting the values

Weight of new student = 1592 – 1560 = 32kg

Therefore, the weight of the new student is 32kg.

RS Aggarwal Solutions Class 9 Mathematics Solutions for Mean Median And Mode Of Ungrouped Data Exercise 18A in Chapter 18 - Mean Median And Mode Of Ungrouped Data