Plz help I need it or I’m gonna fail this test
1 answer:
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Answer:
1a
1b
95% of all sample means will fall between
1c
2
Step-by-step explanation:
From the question we are told that
The mean is
The population standard deviation is
The sample size is n = 16
Generally the standard error of the mean is mathematically represented as
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Generally the probability that the sample mean will be between 39 and 48 minutes is
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From the z table the area under the normal curve to the left corresponding to 1.2 and -2.4 is
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and
So
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From the question we are told the confidence level is 95% , hence the level of significance is
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Generally from the normal distribution table the critical value of is
Generally the margin of error is mathematically represented as
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Generally the 95% of all sample means will fall between
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Generally the value which 90% of sample means is greater than is mathematically represented
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Generally from the z-table the critical value of 0.90 is
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Considering question 2
Generally we are told that the standard deviation of the mean to be one fifth of the population standard deviation, this is mathematically represented as
Generally the standard deviation of the sample mean is mathematically represented as
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