Using the normal distribution, it is found that the cut-off time which 75.8% of the college students exceed when trying to find a parking spot in the library parking lot is of 3.7 minutes.
The z-score of a measure X of a normally distributed variable with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex] is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The mean and the standard deviation are given as follows:
[tex]\mu = 4.5, \sigma = 1[/tex]
The cut-off time is the 100 - 75.8 = 24.2th percentile, which is X when Z = -0.7, hence:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-0.7 = \frac{X - 4.5}{1}[/tex]
X - 4.5 = -0.7
X = 3.7.
More can be learned about the normal distribution at https://brainly.com/question/4079902
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