An article in Cancer Research [“Analyses of Litter-Matched Time-to-Response Data, with Modifications for Recovery of Interlitter
Information” (1977, Vol. 37, pp. 3863–3868)] tested the tumorigenesis of a drug. Rats were randomly selected from litters and given the drug. The times of tumor appearance were recorded as follows: 101, 104, 104, 77, 89, 88, 104, 96, 82, 70, 89, 91, 39, 103, 93, 85, 104, 104, 81, 67, 104, 104, 104, 87, 104, 89, 78, 104, 86, 76, 103, 102, 80, 45, 94, 104, 104, 76, 80, 72, 73 Calculate a 95% confidence interval on the standard deviation of time until a tumor appearance. Check the assumption of normality of the population and comment on the assumptions for the confidence interval
1 answer:
Answer:
2.51 < σ < 3.92
Step-by-step explanation:
We will use Chi-Square distribution to create the interval. We have the following information:
n = 41
Level of Confidence : 95%,
This corresponds to Chi-Square values of:
24.433 for the left tail and 59.342 for the right tail
We need to calculate the sample Variance. This is done on attached photo 1 (the shortcut formula for finding variance was used)
We get s = 9.3866.
See the construction of the confidence interval on the second attached photo
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Complete Question:
Kyle held a balloon 8 feet off the ground, straight above his head. Ava is standing 15 feet directly to the right of Kyle.
Write an equation using the Pythagorean Theorem to find the value of x.
How far are Ava's feet from the balloon?
Answer:
Ava's feet is 17ft away from the balloon
Step-by-step explanation:
Given
The attached image represents the scenario
Using Pythagoras theorem (from the attachment), we have:
Take square roots of both sides
