What is -(-5) ? i am so confused
2 answers:
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Answer:
Option b. should not be rejected
Step-by-step explanation:
We are given that the contents of a sample of 26 cans of apple juice showed a standard deviation of 0.06 ounces.
We have to test whether the variance of the population is significantly more than 0.003, i.e.;
Null Hypothesis, :
=
Alternate Hypothesis, :
The test statistics used here for testing variance is;
T.S. = ~
where, s = sample standard deviation = 0.06
n = sample size = 26 cans
So, Test statistics = ~
= 30
So, at 5% level of significance chi square table gives critical value of 37.65 at 25 degree of freedom. Since our test statistics is less than the critical so we have insufficient evidence to reject null hypothesis.
Therefore, we conclude that null hypothesis should not be rejected and variance of population is 0.003.
Answer:
19 beers must be sampled.
Step-by-step explanation:
We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Z-table as such z has a p-value of .
That is z with a pvalue of , so Z = 1.645.
Now, find the margin of error M as such
In which is the standard deviation of the population and n is the size of the sample.
The population standard deviation for the temperature of beers found in Scooter's Tavern is 0.26 degrees.
This means that
If we want to be 90% confident that the sample mean beer temperature is within 0.1 degrees of the true mean temperature, how many beers must we sample?
This is n for which M = 0.1. So
Rounding up:
19 beers must be sampled.