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A factory is operating in two shifts, day and night, with 70 and 30 workers, respectively.If per day mean wage of the day shift workers is, ₹ 54 and per day mean wage of all the workers is ₹ 60 , then per day mean wage of the night shift workers (in ₹ ) is :

Options

  1. A75
  2. B74
  3. C69
  4. D66

Correct answer

B. 74

Step-by-step solution

n 1   x ¯ 1     + n 2   x ¯ 2 n 1 + n 2   =   x ¯ 70 ⋅ 54 + 30   x ¯ 2 70 + 30 = 60 ⇒ 3780 + 30   x ¯ 2   = 6000 ∴       x ¯ 2 =   6000 - 3780 30 =   2220 30 = 74

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