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The length of time, in hours, it takes a group of people, 40 years and older, to play one soccer match is normally distributed with a mean of 2 hours and a standard deviation of 0.5 hours. A sample of size 50 is drawn randomly from the population. Find the probability that the sample mean is less than 2.3 hours. g

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Answer:

[tex]P(\overline X < 2.3) = 0.9999[/tex]

Step-by-step explanation:

Given that:

mean = 2

standard deviation = 0.5

sample size = 50

The probability that the sample mean is less than 2.3 hours is :

[tex]P(\overline X < 2.3) = P(Z \leq \dfrac{\overline x - \mu}{\dfrac{\sigma}{\sqrt{n}}})[/tex]

[tex]P(\overline X < 2.3) = P(Z \leq \dfrac{2.3 - 2.0}{\dfrac{0.5}{\sqrt{50}}})[/tex]

[tex]P(\overline X < 2.3) = P(Z \leq \dfrac{0.3}{0.07071})[/tex]

[tex]P(\overline X < 2.3) = P(Z \leq 4.24268)[/tex]

[tex]P(\overline X < 2.3) = P(Z \leq 4.24)[/tex]

From z tables;

[tex]P(\overline X < 2.3) = 0.9999[/tex]

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