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The marks obtained by 51 students in a class are in AP with its first term 4 and common difference 3 . What is the mean of the marks?

Options

  1. A67
  2. B71
  3. C75
  4. D79

Correct answer

D. 79

Step-by-step solution

aligned & S_n= n 2 [2 a+(n-1) d] & = 51 2 [8+50 3]= 51 158 2 =51 79 aligned Mean == S _ n n = 51 79 51 =79

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