Students of three sections of a class, having 30,30 and 40 students...

Students of three sections of a class, having 30,30 and 40 students appeared for a test of 100 marks. The arithmetic means of the marks of the three sections are

72.2,69.0

and 64.1 in that order. What is the arithmetic mean of the marks of all the students of three sections?

Options

A $66.6$
B $67.3$
C $68.0$
D $70.6$

Correct answer

C. $68.0$

Step-by-step solution

The correct answer is option C

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