IQR is the Q3 - Q1
Put the data in order.....
6, 7, 11, 13, 14, 15, 15, 19, 21
^ ^ ^
9(Q1) 14(Q2) 17(Q3)
17 (Q3) - 9 (Q1) = 8 (IQR)
So the answer to your question is the first option, 8.
Hope this helps! :D

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<em>"Associate with people who are likely to improve you."</em>
Answer:
2.27700622339
Step-by-step explanation:
Calculated your welcome
Answer:
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Step-by-step explanation:
![\sqrt[n]{a^m}=a^\frac{m}{n}\\\\\text{therefore}\\\\\sqrt[3]{c^4}=c^\frac{4}{3}](https://tex.z-dn.net/?f=%5Csqrt%5Bn%5D%7Ba%5Em%7D%3Da%5E%5Cfrac%7Bm%7D%7Bn%7D%5C%5C%5C%5C%5Ctext%7Btherefore%7D%5C%5C%5C%5C%5Csqrt%5B3%5D%7Bc%5E4%7D%3Dc%5E%5Cfrac%7B4%7D%7B3%7D)