Answer:
10.75
Explanation:
Interquartile R range of an ungrouped data is expressed as R = Q3-Q1 where;
Q3 is the third quartile
Q1 is the first quartile
Given the Car Dealership Number of Cars Sold GMC as 84 Chevrolet 81 Nissan 92 Toyota 92 Ford 95 Honda 94 Hyundai 80 Acura 72
First let us arrange them in ascending order;
72, 80, 81, 84, 92, 92, 94, 95
Q3 = 3(n+1)/4 th observation where n is the total number of cars
Q3 = 3(8+1)/4 = 27/4
Q3 = 6.75th observation
Q3 = 6th obsrvation - 0.75(7th observation - 6th observation)
Q3 = 92-0.75(94-92)
Q3 = 92-0.75(2)
Q3 = 90.5
The 6.75th observation of the data is 90.5
Q1 = (n+1)/4 th observation where n is the total number of cars
Q1 = (8+1)/4 = 9/4
Q1 = 2.25th observation
Q1 = 2nd observation - 0.25(3rd observation - 2nd observation)
Q1 = 80-0.25(81-80)
Q1 = 80-0.25(1)
Q1 = 79.75
Interquartile range = Q3 - Q1
Interquartile range = 90.5 - 79.75
Interquartile range = 10.75