Question

In the data set below, what are the lower quartile, the median, and the upper quartile?
3 4 4 4 4 6 7 8 8 9
lower quartile =


median =


upper quartile =

Answer 1

Sort check (already sorted): 3 4 4 4 4 6 7 8 8 9 (n = 10)

Median = average of 5th and 6th values = (4 + 6)/2 = 5.

Lower half (first 5 values): 3, 4, 4, 4, 4 → lower quartile (median of these) = 4.

Upper half (last 5 values): 6, 7, 8, 8, 9 → upper quartile (median of these) = 8.

So:
lower quartile = 4
median = 5
upper quartile = 8