A county with a large population need to know what the average income is for tax purposes. A simple random sample of 1000 household reveals the following information. The average household income for the sample is $21,000. The median income of the sample is $17,000. The SD of the sample is $10,000, Q1 = $11,000 and Q3 = $24,000.
What is the interquartile range of the data?
The interquartile range (IQR) is a measure of the dispersion of the middle 50% of the data. It is calculated by subtracting the first quartile (Q1) from the third quartile (Q3).
Q1 = $11,000
Q3 = $24,000
IQR = Q3 - Q1
= $24,000 - $11,000
= $13,000
Therefore, the interquartile range of the data is $13,000.