Question
In a class of 40 students, the
average weight of the class is 65 kg, but when one of the students left from the school and 6 new students joined the class such that the average weight of the class becomes 64.8 kg. What is the weight of a student who is 3 kg more than the weight of the student who left from the school, if the total weight of six new students who joined the class is 390 kg?Solution
ATQ, Sum of weight of class = 40 * 65 = 2600 2600 - x + 390 = 64.8 * 45 2990 - x = 2916 x = 74 Required weight of the student = 74 + 3 = 77 kg
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