Figuratively speaking, the sequential sequence is put into a box and then divided into four equal parts. The position of the lower cutter is quartile (Q), and the quartile spacing (IQR) is Q3-Q 1 (large fraction-small fraction).

Q: Why is the answer 17?

First order:192122 28 3133 44 50.

First find the median =Q2=28, and then confirm Q 1, Q3.

q 1 =(22+2 1)/2 = 2 1.5

Q3= (33+44)/2= 38.5

IQR = 38.5-2 1.5 = 17

Question 2: Even numbers.

Example 1:

For example, add a 19 to the above question.

19 19 2 1 22 22 28 3 1 33 44 50

Q2=(22+28)/2=25

Q 1=2 1

Q3=33

IQR=33-2 1= 12

Example 2: 1 2 3 4

Q2=(2+3)/2 = 2.5

q 1 =( 1+2)/2 = 1.5

Q3=(3+4)/2=3.5

IQR= 3.5- 1.5=2