Question
The average weight of 6 students in a group is 45 kg. If
one student is replaced by person 'B', the average weight of the group increases by 5%. Find the difference between the weight of the student who left and the weight of person 'B'.Solution
ATQ,
Total weight of the group = 45 × 6 = 270 kg
New average weight of the group = 45 × 1.05 = 47.25 kg
So, total weight of the group = 47.25 × 6 = 283.5 kg
So, difference between weights of the student who left and person 'B' =
283.5 - 270 = 13.5 kg
Alternate Solution—
Required difference = 0.05 × 45 × 6 = 13.5 kg
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