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JEE Main20265 April 2026Morning ShiftMathematicsStatisticsActual

The mean deviation about the mean for the data x_i 5 7 9 10 12 15 f_i 8 6 2 2 2 6 is equal to:

Options

  1. A40 13
  2. B42 13
  3. C44 13
  4. D46 13

Correct answer

C. 44 13

Step-by-step solution

Mean x = f_i x_i f_i f_i = 8 + 6 + 2 + 2 + 2 + 6 = 26 f_i x_i = 8(5) + 6(7) + 2(9) + 2(10) + 2(12) + 6(15) f_i x_i = 40 + 42 + 18 + 20 + 24 + 90 = 234 x = 234 26 = 9 Mean deviation about mean = f_i |x_i - x | f_i f_i |x_i - x | = 8|5 - 9| + 6|7 - 9| + 2|9 - 9| + 2|10 - 9| + 2|12 - 9| + 6|15 - 9| f_i |x_i - x | = 8(4) + 6(2) + 2(0) + 2(1) + 2(3) + 6(6) f_i |x_i - x | = 32 + 12 + 0 + 2 + 6 + 36 = 88 Mean deviation = 88 26 = 44 13 Answer: 44 13

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