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The set Q consists of 15 numbers whose arithmetic mean is
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12 Nov 2020, 10:48
12 Nov 2020, 10:48
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The set Q consists of 15 numbers whose arithmetic mean is zero. Which of the following quantities must also be zero?
Indicate all such quantities.
A. The median of the numbers in Q
B. The mode of the numbers in Q
C. The sum of the numbers in Q
Source: 320 GRE Math Questions
Indicate all such quantities.
A. The median of the numbers in Q
B. The mode of the numbers in Q
C. The sum of the numbers in Q
Source: 320 GRE Math Questions
Re: The set Q consists of 15 numbers whose arithmetic mean is
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17 Nov 2020, 04:28
17 Nov 2020, 04:28
1
unless we are given information about the distribution of a series, we cannot have a clear idea about the MEDIAN and MODE of that series.
(for uniform series, for example, normal distribution mean=median and same goes mode).
We know the average of any series= SUM/n, the average to be zero the sum must be zero. i.e. SUM=0.
Therefore, C would be the only answer.
(for uniform series, for example, normal distribution mean=median and same goes mode).
We know the average of any series= SUM/n, the average to be zero the sum must be zero. i.e. SUM=0.
Therefore, C would be the only answer.
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Re: The set Q consists of 15 numbers whose arithmetic mean is
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05 Aug 2022, 23:47
05 Aug 2022, 23:47
Theory
The set Q consists of 15 numbers whose arithmetic mean is zero
Sum of 15 numbers = Average * 15 = 0*15 = 0
Lets take each answer choice and analyze
A. The median of the numbers in Q
We cannot answer this as we just know that the mean and sum are 0. We do not know anything else about the dataset. So, we cannot say anything about the mean.
Some possible data sets are
1) -105, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14
2) All of them are 0
Clearly, we cannot find the median
B. The mode of the numbers in Q
We cant find the mode also there are multiple options for the dataset
C. The sum of the numbers in Q
Proved above
So, Answer will be C.
Hope it helps!
Watch the following video to Learn the Basics of Statistics
- ➡ Average = Sum of all the Values / Total Number of Values
➡ Sum of all the Values = Average * Total Number of Values
➡ In case of even number of numbers in the set: Median is the mean of the two middle numbers (after the numbers are arranged in the increasing / decreasing order)
➡ In case of odd number of numbers in the set: Median is the middle number (after the numbers are arranged in increasing/ decreasing order)
➡ Mode is the number which has occurred the maximum number of times in the set.
The set Q consists of 15 numbers whose arithmetic mean is zero
Sum of 15 numbers = Average * 15 = 0*15 = 0
Lets take each answer choice and analyze
A. The median of the numbers in Q
We cannot answer this as we just know that the mean and sum are 0. We do not know anything else about the dataset. So, we cannot say anything about the mean.
Some possible data sets are
1) -105, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14
2) All of them are 0
Clearly, we cannot find the median
B. The mode of the numbers in Q
We cant find the mode also there are multiple options for the dataset
C. The sum of the numbers in Q
Proved above
So, Answer will be C.
Hope it helps!
Watch the following video to Learn the Basics of Statistics
