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The average (arithmetic mean) of all the positive multiples
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25 Apr 2017, 02:56
25 Apr 2017, 02:56
Expert Reply
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Question Stats:
80% (00:46) correct
19% (00:39) wrong based on 226 sessions
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Quantity A |
Quantity B |
The average (arithmetic mean) of all the positive multiples of 5 less than 26 |
The average (arithmetic mean) of all the positive multiples of 7 less than 26 |
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 all the positive multiples
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09 Oct 2017, 07:40
09 Oct 2017, 07:40
2
This question can be solved by computing the averages on quantity A, i.e. 5+10+15+20+25/5 = 15 and on quantity B, i.e. 7+14+21/3 = 14. Answer A.
To be even faster, one can notice that in evenly spaces sets the median and the mean coincide, so that we just have to write down the elements of each set and take the central one (since the number of elements is odd). This way we have to compare 15 and 14, thus answer A
To be even faster, one can notice that in evenly spaces sets the median and the mean coincide, so that we just have to write down the elements of each set and take the central one (since the number of elements is odd). This way we have to compare 15 and 14, thus answer A
Re: The average (arithmetic mean) of all the positive multiples
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02 Apr 2018, 12:14
02 Apr 2018, 12:14
1
Answer: A
A: Multiples of 5 less than 26 are: 5, 10, 15, 20, 25
As each of the values is result of a constant value to previous object in sequence, their average is: (a1 +an)/2 = (5 + 25) / 2 = 15
B: The positive multiples of 7 less than 26 are: 7, 14, 21
As each of the values is result of a constant value to previous object in sequence, their average is: (a1 +an)/2 = (7 + 21) / 2 = 14
A is bigger than B
A: Multiples of 5 less than 26 are: 5, 10, 15, 20, 25
As each of the values is result of a constant value to previous object in sequence, their average is: (a1 +an)/2 = (5 + 25) / 2 = 15
B: The positive multiples of 7 less than 26 are: 7, 14, 21
As each of the values is result of a constant value to previous object in sequence, their average is: (a1 +an)/2 = (7 + 21) / 2 = 14
A is bigger than B
