The answer is 5.
Explanation:
To find the interquartile range you must look at the median and the upper and lower halves of the data. The median (12) to the upper half of the data (15) is 3. Next, look at the median (12) to the lower half of the data (10) it is 2. We then add 2 and 3 to get the interquartile range of 5.