The average weight of a group of 5 friends is 70 kg. If one person with a weight of 70 kg joins the group. what is the new average weight?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 70 kg.
Given that, average weight of 5 friends = 70 kg
Total weight = Average weight × number of persons
According to the given question,
Total weight of 5 friends = 70 × 5
⇒ 350 kg
Weight of the new person = 70 kg
Total weight of 6 persons = 350 + 70
⇒ 350 + 70 = 420 kg
Average weight of 6 persons =
⇒ 70 kg
Hence the new average weight is 70 kg.