Options:
A. 18, 20, 20, 22, 25
B. 20, 20, 20, 25, 25
C. 16, 19, 21, 22, 22
D. 20, 20, 21, 22, 22
Answer:
A. 18, 20, 20, 22, 25
Step-by-step explanation:
Required
Which list has a mean of 21 and median of 20
Each of the list have 5 numbers and they've all been sorted.
The median is the number at the 3rd position (i.e. the middle number)
So, list C and D are out because they do not have a median of 20.
Next, calculate the mean of lists A and B
[tex]\bar x = \frac{\sum x}{n}[/tex]
A. 18, 20, 20, 22, 25
[tex]\bar x = \frac{18 + 20 + 20 + 22 + 25}{5}[/tex]
[tex]\bar x = \frac{105}{5}[/tex]
[tex]\bar x = 21[/tex]
B. 20, 20, 20, 25, 25
[tex]\bar x = \frac{20 + 20 + 20 + 25 + 25}{5}[/tex]
[tex]\bar x = \frac{110}{5}[/tex]
[tex]\bar x = 22[/tex]
Only list A has a median value of 20 and a mean value of 21
