find the first quartile of 7,8,7,9,11,8,7,9,6 and 8.
A
8.5
B
7.0
C
7.5
D
8.0
Verified Correct Answer: B.
Step-by-Step Mathematical Solution
Rearrange data in increasing order: 6,7,7,7,8,8,8,9,9 and 11
First quartile (ungrouped data) = \(\frac{n + 1}{4}\)th value
= \(\frac{11}{4}\)
= 2.75th value
= \(\frac{7 + 7}{2}\)
= 7.0
Source: WAEC / JAMB / NECO Classroom Archive (Record #61424)