Is the mean lifetime of particular type of car engine greater than 350,000 km? To test this claim,a sample of 23 engines is measured,yielding an average of 365,000 km and a standard deviation of 18,500 km.Use a significance level of 0.01.

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To determine if the mean lifetime of the car engines is greater than 350,000 km, we perform a one-sample t-test. The null hypothesis (H0) is μ = 350,000 km, and the alternative hypothesis (H1) is μ > 350,000 km. Using the given sample mean (365,000 km), sample standard deviation (18,500 km), sample size (23), and the significance level (α = 0.01), we calculate the t-statistic and corresponding P-value. The correct choice must show a rejection of the null hypothesis with a P-value less than the significance level, indicating sufficient evidence that the engines last longer than 350,000 km on average. Choice C correctly indicates a rejection of the null hypothesis with a very low P-value, suggesting strong evidence against the null hypothesis in favor of the alternative.

Is the Mean Lifetime of Particular Type of Car Engine