The average weight of six persons is 30 kg. If a new person joins this group, then the average weight becomes 28 kg. What is the weight of the new person?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. 16 kg.
Let, the sum of weights of all the six persons be W
We know that,
Average = Sum of observations/Number of observations
W/6 = 30
⇒ W = 180
Now if the new person joins the group whose weight is 'x'
⇒ (W + x)/7 = 28
⇒ 180 + x = 196
Thus,
The weight of the new person = 16 kg