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Chapter 4: Q118E (page 268)

Consider a sample data set with the following summary

statistics: s= 95, QL = 72, QU = 195.

a. Calculate IQR.

b. Calculate IQR/s.

c. Is the value of IQR/sapproximately equal to 1.3? Whatdoes this imply?

Short Answer

Expert verified

a. The value of IQR is 123

b. The value of IQR/s is 1.3

c. The value of IQR/s is approximately 1.3, implies that the data is normally distributed.

Step by step solution

01

Given Information

The summary statistics are given by,

s=95,QL=72,QU=195

02

Calculating IQR

a.

The IQR is,

IQR=QU-QL=195-72=123

Thus, the IQR is 123.

03

Calculating IQR/s

b.

IQRs=12395=1.294737𝆏1.3

Thus, the IQR/s is 1.3.

04

Interpretation of IQR/s

C.

Here the value of IQR/s is approximately 1.3. This means that the data is normally distributed.

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