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The average (arithmetic mean) of x, y, and z
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30 Aug 2018, 07:29
30 Aug 2018, 07:29
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Expert Reply
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Question Stats:
48% (00:49) correct
51% (00:38) wrong based on 129 sessions
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Quantity A |
Quantity B |
The average (arithmetic mean) of x, y, and z |
The average (arithmetic mean) of 0.5x, 0.5y, and 0.5z |
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 x, y, and z
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15 Oct 2018, 09:08
15 Oct 2018, 09:08
1
Answer is (D). The average of x, y, and z is . Calculated similarly, the average of 0.5x, 0.5y, and
0.5z is exactly half that. If the sum of the variables is positive, Quantity A is greater. However, if the
sum of the variables is negative, Quantity B is greater. If the sum of the variables is zero, the two
quantities are equal.
0.5z is exactly half that. If the sum of the variables is positive, Quantity A is greater. However, if the
sum of the variables is negative, Quantity B is greater. If the sum of the variables is zero, the two
quantities are equal.
Re: The average (arithmetic mean) of x, y, and z
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13 Jan 2019, 22:49
13 Jan 2019, 22:49
Expert Reply
plug in 10, 20,30
(10+20+30)/3= 60/3= 20
do the same for Quantity B and we get
(5+10+15)/3= 30/3 =10
So here, quantity A looks greater
then plug in the negative versions for Quantity A
(-10+-20+-30)/3= -20
Plug in the negative versions for Quantity B
(-5+-10+-15)/3= -10
-10 is greater than -20, which is the opposite of when the numbers are positive.
since A is greater when the numbers are positive, and B is greater when the numbers are negative,
we have an inconsistent solution, and choose D
(10+20+30)/3= 60/3= 20
do the same for Quantity B and we get
(5+10+15)/3= 30/3 =10
So here, quantity A looks greater
then plug in the negative versions for Quantity A
(-10+-20+-30)/3= -20
Plug in the negative versions for Quantity B
(-5+-10+-15)/3= -10
-10 is greater than -20, which is the opposite of when the numbers are positive.
since A is greater when the numbers are positive, and B is greater when the numbers are negative,
we have an inconsistent solution, and choose D
