8. the following data set represents the cost of an order (rounded to the nearest dollar) in a fast - food…

8. the following data set represents the cost of an order (rounded to the nearest dollar) in a fast - food drive thru. 10, 21, 34, 12, 6, 3, 14, 18, 22, 29, 9, 2, 15, 12, 18\nq1: \nq3: \niqr:

8. the following data set represents the cost of an order (rounded to the nearest dollar) in a fast - food drive thru. 10, 21, 34, 12, 6, 3, 14, 18, 22, 29, 9, 2, 15, 12, 18\nq1: \nq3: \niqr:

Answer

Explanation:

Step1: Sort the data set

First, sort the data set (3,6,9,10,12,14,15,18,18,21,22,29) in ascending - order. There are (n = 12) data points.

Step2: Find the first - quartile (Q1)

The position of Q1 is (i=\frac{n + 1}{4}=\frac{12+1}{4}=3.25). So, (Q1=9+(0.25)\times(10 - 9)=9.25).

Step3: Find the third - quartile (Q3)

The position of Q3 is (i = \frac{3(n + 1)}{4}=\frac{3\times(12 + 1)}{4}=9.75). So, (Q3=18+(0.75)\times(21 - 18)=20.25).

Step4: Calculate the inter - quartile range (IQR)

The inter - quartile range (IQR=Q3 - Q1). Substitute (Q1 = 9.25) and (Q3=20.25) into the formula: (IQR=20.25−9.25 = 11).

Answer:

Q1: (9.25) Q3: (20.25) IQR: (11)