Standard Normal Distribution 04 Step 1: Select one-tailed or two-tailed. O One-tailed 0.3+ O Two-tailed Step 2: Enter the critical value(s). (Round to 3 decimal places.) 0.2+ 0.1+ Step 3: Enter the...

Extracted text: Standard Normal Distribution 04 Step 1: Select one-tailed or two-tailed. O One-tailed 0.3+ O Two-tailed Step 2: Enter the critical value(s). (Round to 3 decimal places.) 0.2+ 0.1+ Step 3: Enter the test statistic. (Round to 3 decimal places.) 1 -2 s ? (d) Based on your answer to part (c), choose what can be concluded, at the 0.10 level of significance, about the proportion of all dentists who now recommend the brand. 2.


Extracted text: According to a report done last year by the dental industry, 81% of dentists would recommend Starry Whites toothpaste. After some recent negative publicity, the sales team at Starry Whites suspects the proportion of dentists who now recommend the brand is lower. The team chooses 150 dentists at random and asks them whether they'd recommend the brand. Of those, 118 say they'd recommend it. Complete the parts below to perform a hypothesis test to see if there is enough evidence, at the 0.10 level of significance, to conclude that the proportion, p, of all dentists who now recommend this brand is less than 81%. (a) State the null hypothesis Ho and the alternative hypothesis H, that you would use for the test. ( Ho: Aa O 10 under the assumption that the null hypothesis is true.) Here n is the sample size and p is the population proportion you are testing.