Answer:
n = 1.125
Step-by-step explanation:

(Use Cross Product)
40n = 15 × 3
40n = 45
n = 1.125
The hypothesis test shows that we reject the null hypothesis and there is sufficient evidence to support the claim that the return rate is less than 20%
<h3>What is the claim that the return rate is less than 20% by using a statistical hypothesis method?</h3>
The claim that the return rate is less than 20% is p < 0.2. From the given information, we can compute our null hypothesis and alternative hypothesis as:


Given that:
Sample size (n) = 6965
Sample proportion 
The test statistics for this data can be computed as:



z = -2.73
From the hypothesis testing, since the p < alternative hypothesis, then our test is a left-tailed test(one-tailed.
Hence, the p-value for the test statistics can be computed as:
P-value = P(Z ≤ z)
P-value = P(Z ≤ - 2.73)
By using the Excel function =NORMDIST (-2.73)
P-value = 0.00317
P-value ≅ 0.003
Therefore, we can conclude that since P-value is less than the significance level at ∝ = 0.01, we reject the null hypothesis and there is sufficient evidence to support the claim that the return rate is less than 20%
Learn more about hypothesis testing here:
brainly.com/question/15980493
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Answer:
5.66 years
Step-by-step explanation:
450 x 1.025^(n) = 450 + 67.50
450 x 1.025^(n) = 517.50
1.025^(n) =(517.50 / 450)
1.025^(n) = 1.15
n = ln(1.15) / ln(1.025)
n = 5.66
To calculate expected value,
We can add up the probability of all possible events.
The 2 possible events are either winning $50 or losing the prize, which is $ - 50
Expected value =
50 x 40 % + (-50) x 60%
= $-10
So the answer is $-10
Answer:
1 5/9
Step-by-step explanation: