Answer: 8
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Work Shown:
Original set = {5.5, 6.5, 7.6, 8.5, 4.75, 8, 6.25, 6, 8.5, 7.75}
Sorted set = {4.75, 5.5, 6, 6.25, 6.5, 7.6, 7.75, 8, 8.5, 8.5}
There are n = 10 values. Split the data in half to have n/2 = 10/2 = 5 items per half.
L = Lower set of values smaller than the median
L = {4.75, 5.5, 6, 6.25, 6.5}
U = upper set of values larger than the median
U = {7.6, 7.75, 8, 8.5, 8.5}
Set L and set U both have 5 values inside them.
The values 6.5 and 7.6 are both tied for the middle-most position. The midpoint of them is the median.
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Q1 = first quartile = lower quartile
Q3 = third quartile = upper quartile
The median of set L will get us the value of Q1.
The median of set U is the value of Q3.
The median of set U in this case is 8, so Q3 = 8 is the upper quartile.