Question

The mean weight of 30 students of s class is 60.2kg . Two students of weight 50 kg and 67 kg left the class .find the mean weight of remaining
Student

Answer 1

Answer :

The mean weight of the remaining students = 60.32

Explanation :

We are given :

• Mean weight of 30 students in a class = 60.2 kg
• Two students of weight 50 kg and 67 kg left the class.

Need to find :

• Mean weight of the remaining students

Solution :

Firstly, we will calculate the sum of the weight of 30 students :

Using formula,

• Mean = (Sum of the weight of 30 students) ÷ No. of students

Substituting the given values :

→ 60.2 = Sum of the weight of 30 students ÷ 30

→ 60.2 × 30 = Sum of the weight of 30 students

→ 602/10 × 30 = Sum of the weight of 30 students

→ 602 × 30 = Sum of the weight of 30 students

→ 1806 = Sum of the weight of 30 students

• The sum of weight of 30 students = 1806

Now, we will calculate the sum of weight of the students who left the class :

→ Total weight = 50 + 67

→ Total weight = 117

The sum of weight of 2 students who left the class = 117

2 students left the class, so now there are total 28 students left in the class $.$

Sum of the weight of 28 students = Sum of weight of 30 students - Sum of weight of 2 students

→ Sum of weight of 28 students = 1806 - 117 = 1689

Therefore, the sum of weight of 28 students = 1689

Now, we can calculate the mean of 28 students :

Using formula,

• Mean = Sum of weight of 28 students ÷ No. of students

Substituting the given values :

→ Mean = 1689 ÷ 28

→ Mean = 60.32

Therefore, the mean weight of the remaining students = 60.32