Question

A class has 60 students of which 25 are taught by teacher A and 35 are taught by teacher B. The class average (mean) mark for all the students is x ¯ x¯ and the mean mark for the students taught by teacher A is x ¯ A x¯A . The mean mark for students taught by teacher B x ¯ B x¯B is

Answer 1

Answer:

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