Question

1a. Silicone implant augmentation rhinoplasty is used to correct congenital nose deformities. The success of the procedure depends on various biomechanical properties of the human nasal periosteum and fascia. An article reported that for a sample of 17 (newly deceased) adults, the mean failure strain (%) was 26.0, and the standard deviation was 3.1.

(a) Assuming a normal distribution for failure strain, estimate true average strain in a way that conveys information about precision and reliability. (Use a 95% confidence interval. Round your answers to two decimal places.)

(____%, ______%)

b)Predict the strain for a single adult in a way that conveys information about precision and reliability. (Use a 95% prediction interval. Round your answers to two decimal places.)

(___%,___%)

2b.

Determine the t critical value for a lower or an upper confidence bound in each of the following situations. (Round your answers to three decimal places.) (a) Confidence level = 95%, df = 10 (b) Confidence level = 95%, df = 20 (c) Confidence level = 99%, df = 20 (d) Confidence level = 99%, n = 10 (e) Confidence level = 97.5%, df = 22 (f) Confidence level = 99%, n = 34

Thank you so much for your help in advance!

Answer 1

Refer t-table or use excel function "=T.INV.2T(0.05,16)" to find the critical value of t

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Use excel formula "=T.INV(Confidence level, df)"

	Confidence level	n	df=n-1	Excel formula	t critical value
	95%		10	=T.INV(0.95,10)
	95%		20	=T.INV(0.95,20)
	99%		20	=T.INV(0.99,20)
	99%	10	9	=T.INV(0.99,9)
	97.5%		22	=T.INV(0.975,22)
	99%	34	33	=T.INV(0.99,33)