sasha needs an average of 30 points to move to the next level in her competion . her scores in the first three events are 28, 35
1 answer:
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Answer:
There is enough evidence to support the claim that the population mean is greater than 100
Step-by-step explanation:
<u>Step 1</u>: We state the hypothesis and identify the claim
and
(claim)
<u>Step 2</u>: Calculate the test value.
<u>Step 3</u>: Find the P-value. The p-value obtained from a calculator is using d.f=39 and test-value 1.126 is 0.134
<u>Step 4</u>: We fail to reject the null hypothesis since P-value is greater that the alpha level. (0.134>0.05).
<u>Step 5</u>: There is enough evidence to support the claim that the population mean is greater than 100.
<u>Alternatively</u>: We could also calculate the critical value to obtain +1.685 for and d.f=39 and compare to the test-value:
The critical value (1.685>1.126) falls in the non-rejection region. See attachment.
NB: The t- distribution must be used because the population standard deviation is not known.
Answer:
Sample size n = 1382
so correct option is D) 1382
Step-by-step explanation:
given data
confidence level = 99 %
margin of error = 3%
probability = 25 %
to find out
How large a sample size needed
solution
we know here P = 25 %
so 1 - P = 1 - 0.25
1 - P = 0.75
and we know E margin of error is 0.03 so value of Z for 99%
α = 1 - 99% = 1 - 0.99
α = 0.01
and =
= 0.005
so Z is here
= 2.576
so
sample size will be
Sample size n =
put here value
Sample size n = (\frac{2.576}{0.03})^2 * 0.25 * 0.75
Sample size n = 1382
so correct option is D) 1382