Question
The average weight of 6 people is 80 kg. When two new
people with their weights in the ratio 2:3 joined the group, the average weight of all the people remains the same. Find the difference between the weights of the two new people who joined the group.Solution
ATQ, Sum of the weight of 6 people = 80 × 6 = 480 kg Sum of the weights of all the people including the ones who joined later = 80 × 8 = 640 kg Total weight of two new people = 640 - 480 = 160 kg Let the weight of two new people who joined the group be '2w' kg and '3w' kg, respectively. 2w + 3w = 160 Or, 'w' = (160/5) = 32 So, required difference = 3w - 2w = w = 32 kg
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