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Mrac [35]
3 years ago
7

A physical fitness association is including the mile run in its secondary-school fitness test. The time for thisevent for boys i

n secondary school is known to possess a normal distribution with a mean of 460 seconds and a standard deviation of 60 seconds. Find the probability that a randomly selected boy in secondary school can run the mile in less than 322 seconds.
Mathematics
1 answer:
valentina_108 [34]3 years ago
6 0

Answer:  0.0107

Step-by-step explanation:

Given : The time for the event for boys in secondary school is known to possess a normal distribution with

\mu=460\text{ seconds}\\\\\sigma=20\text{ seconds}

Let x be the random variable that represents the time for mile run in its secondary-school fitness test.

z-score : \dfrac{x-\mu}{\sigma}

z=\dfrac{322-460}{60}=-2.3

Now, the probability that a randomly selected boy in secondary school can run the mile in less than 322 seconds is given by :-

P(x

Hence, the probability that a randomly selected boy in secondary school can run the mile in less than 322 seconds = 0.0107

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