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The average weight of 36 students is 50 Kg. It was found later that 16 Aug 2021, 04:15
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84% (01:30) correct 16% (02:08) wrong based on 83 sessions

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The average weight of 36 students is 50 Kg. It was found later that the figure of 37 Kg was misread as 73 Kg. What is the correct average?

(A) 49 Kg
(B) 50.5 Kg
(C) 51 Kg
(D) 51.5 Kg
(E) 2 Kg
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A
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The average weight of 36 students is 50 Kg. It was found later that 16 Aug 2021, 05:46
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Sum of the weight of 36 students = 36 * 50 = 1800 kg.

37 misread as 73 must have inflated the sum by a value of 73 -37 = 36kg

Hence the corrected sum = 1800 -36 = 1764 kg

The corrected average = 1764 / 36 = 49 kg

(option a)

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The average weight of 36 students is 50 Kg. It was found later that 16 Aug 2021, 22:48
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Sum of the ages of 36 students = 50*36 = 1800

Now let's reduce the wrong weight and add the correct weight

=> 1800-73+37 = 1764

New average age = 1764/36 = 49

OA should be A
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The average weight of 36 students is 50 Kg. It was found later that 17 Aug 2021, 00:12
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Since 37 was read as 73 (37 - 73 = -36) has to be reduced which will affect all 36 students.

The correct average will be reduced by \(\frac{36 }{ 36} = 1\)

Correct average: 50 - 1 = 49

Answer A
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The average weight of 36 students is 50 Kg. It was found later that 17 Aug 2021, 01:30
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Given -> Average: 50 for 36 students.
Incorrect measurement : 73 instead of 37 -> implies -> +36 incorrectly added.

Average means that if all had the same weight then we can assign each individual the average weight i.e. 50. So, continuing with the same thought, if I have incorrectly added +36 hence for each individual I have added -> extra/(total number of entities) -> 1 added extra to each entity.

Hence, the correct average should be the current average - 1 = 49.
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The average weight of 36 students is 50 Kg. It was found later that 31 Dec 2024, 15:12
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