here are the ages of 13 people in a coffee shop on a given day: 26, 44, 22, 28, 55, 32, 15, 39, 54, 69, 21…

here are the ages of 13 people in a coffee shop on a given day: 26, 44, 22, 28, 55, 32, 15, 39, 54, 69, 21, 18, 48 identify the first quartile by finding the middle number on the left side of the median. if there is no middle number, average the two middle numbers. 15, 18, 21, 22, 26, 28, 32, 39, 44, 48, 54, 55, 69 first quartile (q1) median (q2) third quartile (q3) ?
Answer
Explanation:
Step1: Arrange data in order
$15, 18, 21, 22, 26, 28, 32, 39, 44, 48, 54, 55, 69$
Step2: Find the median position
Since $n = 13$, the median position is $\frac{n + 1}{2}=\frac{13+ 1}{2}=7$th value, which is $32$.
Step3: Consider the left - hand side of the median
The left - hand side data is $15, 18, 21, 22, 26, 28$. There are 6 values.
Step4: Find the middle of the left - hand side data
The middle of 6 values is the average of the 3rd and 4th values. The 3rd value is $21$ and the 4th value is $22$. The average is $\frac{21 + 22}{2}=\frac{43}{2}=21.5$
Answer:
$21.5$