**Answer:**

**first quartile of this data set is 13**

**Step-by-step explanation:**

11, 12, 13, 15, 17, 19, 22, 24, 29, 33, 38

First we find the median for the given set of numbers

Median is the middle number

**11, 12, 13, 15, 17**, 19, **22, 24, 29, 33, 38
**

19 is the median of the set of numbers

First quartile is the median of the set of numbers below 19

third quartile is the median of the set of number above 19

**11, 12, 13, 15, 17**

**Median of 11, 12, 13, 15, 17 is 13**

**So first quartile of this data set is 13**