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NTA Abhyas JEE Main2020MathematicsStatisticsPractice

The average weight of students in a class of 32 students is 40  k g . If the weight of the teacher be included, the average rises by 1 3    k g , then the weight of the teacher is

Options

  1. A40.5 k g
  2. B50 k g
  3. C41 k g
  4. D51 k g

Correct answer

D. 51 k g

Step-by-step solution

Let, the weight of the teacher be w   k g , then 40 + 1 3 = 32 × 40 + w 32 + 1 ⇒ 33 × 40 + 33 × 1 3 = 32 × 40 + w ⇒ w = 51 ∴ Weight of the teacher = 51  k g

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