Answer:
(D) 27.7 minutes
Step-by-step explanation:
The slowest quartile starts at the 75th percentile:
The z-score for the 75th percentile is approximately 0.675. Z-score is given by:
[tex]z=\frac{x-\mu}{\sigma} \\[/tex]
Where 'μ' is the population mean and 'σ' is the standard deviation
At the 75th percentile, the time for a haircut is:
[tex]0.675=\frac{x-25}{4} \\\\x=0.675*4 +25\\x=27.7 \ minutes[/tex]
Therefore, the slowest quartile will require at least 27.7 minutes for a haircut.
