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3 years ago

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A study of 12,000 able-bodied male students at the University of Illinois found that their times for the mile run were approxima

tely Normal with mean 6.88 minutes and a standard deviation of 0.57 minutes. Choose a student at random from this group and call his time for the mile Y. Find P(Y<6) and interpret the result. Follow the four-step process (State, Plan, Do, and Conclude)

1 answer:

den301095 [7]3 years ago

3 0

Answer:

$P (y < 6) = \frac{P(y- \mu)}{\sigma} \mu}{\sigma} \\\\=P(z$

Therefore the probability that a randomly selected student has time for mile run is less than 6 minute is 0.0618

Step-by-step explanation:

Normal with mean 6.88 minutes and

a standard deviation of 0.57 minutes.

Choose a student at random from this group and call his time for the mile Y. Find P(Y<6)

$\mu = 6.88$

$\sigma = 0.57$

y ≈ normal (μ, σ)

The z score is the value decreased by the mean divided by the standard deviation

$P (y < 6) = \frac{P(y- \mu)}{\sigma} \mu}{\sigma} \\\\=P(z$

Therefore the probability that a randomly selected student has time for mile run is less than 6 minute is 0.0618

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