In a survey, 43% of the respondents stated that they talk to their pets on the telephone. A veterinarian believed this result to be too high, so she randomly selected 250 pet owners and discovered that 104 of them spoke to their pet on the telephone. Does the veterinarian have a right to be skeptical? Use the α=0.1 level of significance.Because np0(1−p0)=□□10, the sample size is □5% of the population size, and the sample□ the requirements for testing the hypothesis □ satisfied. (Round to one decimal place as needed.)
Q. In a survey, 43% of the respondents stated that they talk to their pets on the telephone. A veterinarian believed this result to be too high, so she randomly selected 250 pet owners and discovered that 104 of them spoke to their pet on the telephone. Does the veterinarian have a right to be skeptical? Use the α=0.1 level of significance.Because np0(1−p0)=□□10, the sample size is □5% of the population size, and the sample□ the requirements for testing the hypothesis □ satisfied. (Round to one decimal place as needed.)
Calculate Proportion: Calculate the proportion of pet owners in the veterinarian's sample who talk to their pets on the telephone.Calculation: 250 total pet owners104 pet owners=0.416
Set Hypotheses: Set up the null hypothesis (H0) and the alternative hypothesis (H1).H0: p=0.43 (The proportion of all pet owners who talk to their pets on the telephone is 43%)H1: p=0.43 (The proportion of all pet owners who talk to their pets on the telephone is not 43%)
Calculate SE: Calculate the standard error (SE) using the formula SE=p(1−p)/n, where p is the proportion under the null hypothesis and n is the sample size.Calculation: SE=0.43×(1−0.43)/250=0.43×0.57/250=0.2451/250=0.0009804=0.0313
Calculate z-score: Calculate the z-score for the sample proportion to see how far it deviates from the null hypothesis.Calculation: z = \frac{p_{\text{sample}} - p_{\text{null}}}{\text{SE}} = \frac{\(0\).\(416\) - \(0\).\(43\)}{\(0\).\(0313\)} = \(-0.447 \approx −0.45
Determine Critical Value: Determine the critical z-value for a two-tailed test at α=0.1. Since it's a two-tailed test, the critical z-values are approximately ±1.645.
Compare z-scores: Compare the calculated z-score with the critical z-values. Since −0.45 is not less than −1.645 or greater than 1.645, we do not reject the null hypothesis.
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