Question

The mean weight of 5 boys is 42 kg .if a boy having weight 18 kg joins the team then find the mean weight

Answer 1

A.M. = Sum of obs./no. of obs.
=>42kg = Sum / 5
=>42*5= Sum
=>Sum= 210

Now, New Sum = Initial Sum + weight of new boy
= 210+18=228
New mean = new sum/ no. of obs.
= 228/6= 38

I hope that answers the question.
Thanking.

Answer 2

Mean = total weight / total boys
= 42kg = total weight/5
= Total weight = 42 ×5
= 210kg
After change,
Mean = total weight/total boys
= 210+16 /6
= 37.66(approx)