24. A calculus student claims that the average calculus textbook costs at least

Question

24. A calculus student claims that the average calculus textbook costs at least $80 with a standard deviation is S4.00. A sample of 46 books has an average cost of $84 At = o.os, test the student's claim. 25. A child psychologist claims that the average number of mistakes an eight-year-old will make on a skills assessment test is 6 with a standard deviation of 2. A random sample of 49 eight-year-olds had a mean of 7 mistakes. (a) Use P-value to test the psychologist's claim at -0.02. (b) Does the 98% confidence interval contain the actual mean? T-Hypothesis Testing 26. An 224m sample of crankshaft. Engine Crankshaft manufacturing process claims that their engines measure m. Here are the measurements (in millimeters) of a critical dimension on a 224.12 224.00 22402 223.98 223.99 223.96 223-96 224.09 223-99 223.98 223.90 223.98 224.1 224.06 223.91 224.00 (a) State the claim

Explanation / Answer

26. a)

H0:mu<226 (engine measure sless than 224 mm)

H1: mu>=226 (engine measures atleast 224 mm)

c) The test statistic is as follows:

t=(Xbar-mu)/(s/sqrt N-1), where, Xbar is sample mean, s is sample standard deviation and N is sample size.

t=(224.003-224)/(0.063/sqrt 16-1)=0.16

d) The p value is 0.876, which is not less than alpha=0.05. Therefore, fail to reject null hypothesis. There is not sufficient sample evidence to support th eclaim.

Related Questions

Navigate

• Browse (All)
• Browse 2
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.