If the sum of a list of consecutive...

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If the sum of a list of consecutive odd integers is 5, which of the following could be true?

I. The average (arithmetic mean) of the list is equal to 5.
II. The median of the list is equal to 5.
III. The range of the list is equal to 5.

The OA is A.

Can any expert help me with this PS question? Please. Thanks.
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by Jay@ManhattanReview » Mon Oct 23, 2017 3:38 am
LUANDATO wrote:If the sum of a list of consecutive odd integers is 5, which of the following could be true?

I. The average (arithmetic mean) of the list is equal to 5.
II. The median of the list is equal to 5.
III. The range of the list is equal to 5.

The OA is A.

Can any expert help me with this PS question? Please. Thanks.
You forgot to post options.

Let's use brute force, assuming a few odd consecutive integers, such that their sum = 5.

Case 1: The integers are 1 & 3. Not possible since their sum is less than 5.
Case 2: The integers are 1, 3, & 5. Not possible since their sum exceeds 5.
Case 3: The integers are -1, 1, 3, & 5. Not possible since their sum exceeds 5.
Case 4: The integers are -3, -1, 1, 3, & 5. Sum = 5. The only possible case.

Thus, the list contains -3, -1, 1, 3, & 5.

I. The average (arithmetic mean) of the list is equal to 5.

The average (arithmetic mean) of the list = 5/5 = 1. This statement is incorrect.

II. The median of the list is equal to 5.

The median of the list -3, -1, 1, 3, & 5 is 1. This statement is incorrect.

III. The range of the list is equal to 5.

The range of the list -3, -1, 1, 3, & 5 is 5 - (-3) = 8. This statement is incorrect.

No statement is correct.

Hope this helps!

-Jay

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BTGmoderatorLU wrote:
Sat Oct 21, 2017 2:47 pm
If the sum of a list of consecutive odd integers is 5, which of the following could be true?

I. The average (arithmetic mean) of the list is equal to 5.
II. The median of the list is equal to 5.
III. The range of the list is equal to 5.

The OA is A.

Can any expert help me with this PS question? Please. Thanks.
Since the sum of the list of consecutive odd integers is 5, the list of odd integers must be -3, -1, 1, 3, and 5. We see that average is 5/5 = 1, the median is 1, and the range is 5 - (-3) = 8. None of the statements is true.

Answer: None

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