Question

Look at the following data. {18, 19, 31, 5, 12, 16, 18, 19, 5, 30, 31, 16, 32, 31, 39, 26} What is the range of the data?

What is the Interquartile Range (IQR) of the data?

Answer 1

Answer: Range: 34 Interquartile Range: 15

Explanation:

So first, you want to line the numbers up from least to greatest. For example, 5,5,12,16,16,18,18,19,19,26,30,31,31,31,32,39. Now to find the range, you subtract the lowest number from the highest number. 39-5=34. So the range is 34. To find the interquartile range (IQR), ​first find the median (middle value) of the lower and upper half of the data. These values are quartile 1 (Q1) and quartile 3 (Q3). The IQR is the difference between Q3 and Q1. The median is 19. 5,5,12,16,16,18,18,19,19,26,30,31,31,31,32,39. The median of Q1 is 16, and the median of Q3 is 31. 31-16=15. So the (IQR) is 15