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The average (arithmetic mean) of 100 measurements is 23,
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23 Jan 2017, 08:44
23 Jan 2017, 08:44
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Question Stats:
86% (01:00) correct
13% (01:07) wrong based on 219 sessions
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The average (arithmetic mean) of 100 measurements is 23, and the average of 50 additional measurements is 27.
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
Quantity A |
Quantity B |
The average of the 150 measurements |
25 |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
Re: The average (arithmetic mean) of 100 measurements is 23,
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26 Jan 2017, 18:15
26 Jan 2017, 18:15
6
Expert Reply
Explanation
When the average of 100 measurements is 23, find the sum:
sum of 100 numbers/100 = 23 or sum of 100 numbers = 2300.
When the average of 50 measurements is 27, find the sum:
sum of 50 numbers/50 = 27 or sum of 50 numbers = \(50 \times 27\)=1350.
Total of 150 numbers = \(2300 + 1350\)= \(3650\).
Average of 150 number =\(\frac{3650}{150}\)=\(24.55\).
Clearly quantity B is greater. Hence option B is correct.
When the average of 100 measurements is 23, find the sum:
sum of 100 numbers/100 = 23 or sum of 100 numbers = 2300.
When the average of 50 measurements is 27, find the sum:
sum of 50 numbers/50 = 27 or sum of 50 numbers = \(50 \times 27\)=1350.
Total of 150 numbers = \(2300 + 1350\)= \(3650\).
Average of 150 number =\(\frac{3650}{150}\)=\(24.55\).
Clearly quantity B is greater. Hence option B is correct.
General Discussion
Re: The average (arithmetic mean) of 100 measurements is 23,
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17 Sep 2017, 05:01
17 Sep 2017, 05:01
sandy wrote:
Explanation
When the average of 50 measurements is 27, find the sum:
sum of 50 numbers/50 = 27 or sum of 50 numbers = \(50 \times 50\)=1350.
When the average of 50 measurements is 27, find the sum:
sum of 50 numbers/50 = 27 or sum of 50 numbers = \(50 \times 50\)=1350.
It should be \(50 \times 27\)=1350
