Russ19 wrote:
What is the median of the set {a, b, c, d}?
1) The average (arithmetic mean) of a and b is 110.
2) The average (arithmetic mean) of c and d is110.
We know that each statement is insufficient alone because it tells us nothing about the other two terms.
Together, the simplest case is that each term is 110 i.e. the set is {110, 110, 110, 110}
Median is 110.
When we increase-decrease values in one pair, say we get {100, 110, 110, 120} - one value goes to the left of 110 and the other goes to the right. In the middle, we still have 110s so median is 110.
Now try to change the values in the other pair too. When you reduce one number by a certain amount, you will need to increase the other by the same amount.
So if you make them 109 and 111, they will stay in the middle and still add up to 220
{100, 109, 111, 120}
If you make them 105 and 115, they will stay in the middle and still add up to 220
{100, 105, 115, 120}
If you make them 100 and 120, they will stay in the middle and still
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Statistics : Posted by KarishmaB • on 15 Sep 2021, 04:05 • Replies 4 • Views 1635
