Question
The average weight of 20 students is 27 kg. If two
students weighing 19 kg and 47 kg are replaced by a teacher weighing 77 kg, what is the new average weight?Solution
Total weight of all the students in the class, initially = 20 X 27 = 540 kg New total weight of the class = 540 - (19 + 47) + 77 = 551 kg So, new average weight of each student in the class = 551 ÷ 19 = 29 kg
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