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NTA Abhyas JEE Main2020MathematicsStatisticsPractice

The average weight of students in a class of 35 students is 40   k g . If the weight of the teacher is included, then the average rises by 1 3   k g . The weight of the teacher is

Options

  1. A40.5 k g
  2. B50 k g
  3. C41 k g
  4. D52 k g

Correct answer

D. 52 k g

Step-by-step solution

Let, the weight of the teacher be w k g , then 40 + 1 3 = 35 × 40 + w 35 + 1 ⇒ 36 × 40 + 36 × 1 3 = 35 × 40 + w ⇒ w = 5 2 ∴ Weight of the teacher = 52 k g .

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