The average weight of 4 boys is 45 kg. If a new boy with a weight of 55 kg joins them, what is the new average weight of the group?
Show answer & explanation
Correct answer: B
Explanation
Given:
Average weight of 4 boys = 45 kg
Weight of new boy = 55 kg
Formula:
Average = (Total weight) / (Number)
Total weight of 4 boys = 45 × 4 = 180 kg
New total weight = 180 + 55 = 235 kg
Total boys = 5
New average weight = 235 / 5 = 47 kg