Answer:
55.5
Step-by-step explanation:
find the median - in this case it's 60
then group the upper and lower halves of the data:
(11, 19, 35, 42) 60 (72, 80, 85, 88)
now we find the medians of those sets:
35 + 19/2 = 54/2 =27
80 + 85/2 = 165/2 = 82.5
then subtract those two medians to find the interquartile:
82.5 - 27 = 55.5
