16, 24, 30, 34, 50, 64, 66, 66, 80, 99
Step 1: Recall the definition of quartile
DEFINITION: Quartile is median.
Two types: 1) Upper quartile
2) Lower quartile
Upper quartile:
The upper quartile is the median of the higher half of the data.
Lower quartile:
The lower quartile is the median of the lower half of the data.
Step 2: Arrange the numbers from least to greatest.
16, 24, 30, 34, 50, 64, 66, 66, 80, 99 (least to greatest)
Step 3: Separate the numbers into a lower half and an upper half.
16, 24, 30, 34, 50, 64, 66, 66, 80, 99
Lower half: 16, 24, 30, 34, 50
Upper half: 64, 66, 66, 80, 99
Step 4: Find the lower quartile in the lower half
lower quartile in the middle of the lower half.
16, 24, 30, 34, 50
The lower quartile is 30.