If set S consists of even number of integers, is the median of set S negative?
1. Exactly half of all elements of set S are positive.
2. The largest negative element of set S is -1.
Set S
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a)Exactly half of all elements of set S are positive.
(-1, 5) median = +ive
(-1, 0 ) median = -ive
insufficient
b)The largest negative element of set S is -1.
(-1, 5) median = +ive
(-1, 0 ) median = -ive
insufficient
combining a & b - > insufficient
Hence E
(-1, 5) median = +ive
(-1, 0 ) median = -ive
insufficient
b)The largest negative element of set S is -1.
(-1, 5) median = +ive
(-1, 0 ) median = -ive
insufficient
combining a & b - > insufficient
Hence E
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Well, if set S has the even number of terms then the median would be = (sum of 2 middle terms)/2.
We must find then if the absolute value of the left one is greater than the abs of right middle number. Only then we can get a negative median.
1) Absolutely insufficient... it still can be (-1 and 10), or (-100, 1).
2) Ok we know that the largest of the negatives is -1.
Insufficient.
Knowing that there are only integers in the set, 1+2 will be sufficient.
The largest of negatives in -1, left half of the set side also might include 0, or might not. The least of the positive must be at least 1 ( from the given and stmt 1). So, the baddest scenario when the middle positive=1, and middle negative=-1. then the median is 0.
If the left middle number is 0, then the median is positive. So, NO, it is not negative.
We must find then if the absolute value of the left one is greater than the abs of right middle number. Only then we can get a negative median.
1) Absolutely insufficient... it still can be (-1 and 10), or (-100, 1).
2) Ok we know that the largest of the negatives is -1.
Insufficient.
Knowing that there are only integers in the set, 1+2 will be sufficient.
The largest of negatives in -1, left half of the set side also might include 0, or might not. The least of the positive must be at least 1 ( from the given and stmt 1). So, the baddest scenario when the middle positive=1, and middle negative=-1. then the median is 0.
If the left middle number is 0, then the median is positive. So, NO, it is not negative.