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

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

question

what is the value of the third quartile of the data set represented by this box plot? a. 19 b. 21 c. 26 d. 29

answer

c

7 ft 6 in means 7 1/2, because 6 in is 1/2 of a foot. 7 ft 8 in means 7 2/3 because 8 in is 2/3 of a foot. 23/3 = 7 2/3. 15/2 = 7 1/2.

23/3   *   15/2   = 57 1/2

step-by-step explanation: