The mean weight of 120 students of a school is 52.75 kg. If the mean weight of 50 of them is 51 kg, find the mean weight of the remaining students.

Mean weight of 120 students = 52.75 kg Let `a` be the sum of weights of 120 students. Mean weight of 120 students = ⇒ 52.75 = ⇒ a = 120 x 52.75 ⇒ a = 6,330 Mean weight of 50 students = 51 kg Let `b` be the sum of weights of 50 students. ⇒ 51 = ⇒ b = 50 x 51 ⇒ b = 2,550 Sum of weights of remaining (120 - 50) 70 students = 6,330 - 2,550 = 3,780 Mean weight of remaining 70 students = = 54 Hence, the mean weight of remaining 70 students is 54 kg.

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Mathematics

The mean weight of 120 students of a school is 52.75 kg. If the mean weight of 50 of them is 51 kg, find the mean weight of the remaining students.

Statistics

Related Questions

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