Question

The average duration of an NFL football game is 3.25 hours with a standard deviation of .2 hours​ (though only around 11 minutes is playing​ time). Only​ 15% of games last longer than what​ duration? The probability distribution for this data would​ be:

A. Normal Distribution

B. Binomial Distribution

Answer 1

Solution:-

Given that,

mean = = 3.25

standard deviation = = 0.2

A. Normal Distribution

Using standard normal table,

P(Z > z) = 15%

= 1 - P(Z < z) = 0.15  

= P(Z < z) = 1 - 0.15

= P(Z < z ) = 0.85

= P(Z < 1.04 ) = 0.85  

z = 1.04

Using z-score formula,

x = z * +

x = 1.04 * 0.2 + 3.25

x = 3.46 hours