Question

In a class of 100 students, 40% are girls and the remaining are boys. If the average weight of the whole class is 60 and the average of girls is 48 then find the average of Boys?
1. 68 kg
2. 70 kg
3. 72 kg
4. 60 kg
5. 65 kg

Answer 1

Correct Answer - Option 1 : 68 kg

GIVEN:

Total student = 100

Average of whole class = 60

Girls = 40% of Total student

⇒ Average of girls = 48

ASSUMPTION:

Let the average weight of boys = Y

FORMULA USED:

⇒ Average = Sum of observations/number of observations      ----(1)

CALCULATION:

⇒ Sum of observations = 6000

⇒ Girls = 40

⇒ Boys = 60

According to the question

⇒ 40 x 48 + 60 x Y = 6000

⇒ Y = 68

⇒ Average of boys = 68