Answer:
A) 69
Step-by-step explanation:
• First , we put the numbers of the distribution in order:
60 , 66 , 72 , 78 , 80 , 82 , 88 , 90
• Notice that the set has 8 numbers which is an even number.
Then
→ the lower quartile is the mean of the set :
60 , 66 , 72 , 78
Which is the average of the two middle numbers 66 and 72.
Then
[tex]\text{the lower quartile}=\frac{66+72}{2} = 69[/tex]
