Answer: 2
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Step-by-step explanation:
The data set is
{0,0,0,1,2,2,2,2,2,3,4}
The median is the middle-most value. To find it, cross off the outer pair of values until you narrow in on the median of 2. It should be the second copy of it. Check out the diagram below to see what I mean.
Then break up the set into
L = {0,0,0,1,2}
U = {2,2,2,3,4}
Each subset mentioned has 5 items. The diagram below also shows how set L and set U are formed. L is the stuff below the median, aka lower set. Set U is the upper set, which is stuff above the median.
The median of set L is 0, while the median of set U is 2
So we have the first and third quartiles of Q1 = 0 and Q3 = 2
The difference of these is the IQR
IQR = Q3 - Q1 = 2 - 0 = 2
For some reason, the number 2 shows up a lot in this problem.