Question

The distribution of weights (in kg) of 44 students in a class is as follows:

Weight	No. of Students
35 - 38	3
38 - 41	13
41 - 44	13
44 - 47	10
47 - 50	5

What is the average weight of the class?

1. 40.26
2. 41.88
3. 42.56
4. 43.25

Answer 1

Correct Answer - Option 3 : 42.56

Concept used:

Mean and frequency.

Calculation:

Mean of the given data

⇒ (35 + 38)/2 = 36.5 

⇒ (38 + 41)/2 = 39.5 

⇒ (41 + 44)/2 = 42.5 

⇒ (44 + 47)/2 = 45.5 

⇒ (47 + 50)/2 = 48.5  

Average weight of all class

 \(\Rightarrow \frac{{36.5 \times 3 + 39.5 \times 13 + 42.5 \times 13 + 45.5 \times 10 + 48.5 \times 5}}{{44}}\)

⇒ 1873/44

∴ 42.56 is the average of the class.