Correct Answer - Option 1 : 5
Given:
The average weight of the group = 44 kg
Formula used:
\(Average\ =\ {The\ sum\ of\ the\ all\ items \over The\ total\ number\ of\ items}\)
Calculation:
Let us assume the total boys in the group be X
⇒ The sum of the weight of the all-boys = 44X
⇒ 42X = 44X - 50 + 40
⇒ 42X = 44X - 10
⇒ 44X - 42X = 10
⇒ 2X = 10
⇒ X = 5
∴ The required result will be 5.