The manufacturer of a new racecar engine claims that the proportion of engine failures due to overheating for this new engine, (p1)(p1), will be no higher than the proportion of engine failures due to overheating of the old engines, (p2)(p2). To test this statement, NASCAR took a random sample of 120120 of the new racecar engines and 115115 of the old engines. They found that 77 of the new racecar engines and 44 of the old engines failed due to overheating during the test. Does NASCAR have enough evidence to reject the manufacturer's claim about the new racecar engine? Use a significance level of α=0.1α=0.1 for the test.
Step 1 of 6: State the null and alternative hypotheses for the test.
Step 2 of 6: Find the values of the two sample proportions, pˆ1p^1 and pˆ2p^2. Round your answers to three decimal places.
Step 3 of 6: Compute the weighted estimate of p, p‾‾p‾. Round your answer to three decimal places.
Step 4 of 6: Compute the value of the test statistic. Round your answer to two decimal places.
Step 5 of 6: Find the P-value for the hypothesis test. Round your answer to four decimal places.
Step 6 of 6: Make the decision to reject or fail to reject the null hypothesis.
The manufacturer of a new racecar engine claims that the proportion of engine failures due to...
The manufacturer of a new racecar engine claims that the proportion of engine failures due to overheating for this new engine, (p1), will be no higher than the proportion of engine failures due to overheating of the old engines, (p2). To test this statement, NASCAR took a random sample of 120 of the new racecar engines and 110 of the old engines. They found that 14 of the new racecar engines and 8 of the old engines failed due to...
The manufacturer of a new racecar engine claims that the proportion of engine failures due to overheating for this new engine, (p), will be no higher than the proportion of engine failures due to overheating of the old engines, (p). To test this statement, NASCAR took a random sample of 235 of the new racecar engines and 190 of the old engines. They found that 24 of the new racecar engines and I l of the old engines failed due...
The manufacturer of a new racecar engine claims that the proportion of engine failures due to overheating for this new engine, (p1), will be no higher than the proportion of engine failures due to overheating of the old engines, (p2). To test this statement, NASCAR took a random sample of 120 of the new racecar engines and 115 of the old engines. They found that 7 of the new racecar engines and 4 of the old engines failed due to...
The manufacturer of a new racecar engine claims that the proportion of engine failures due to overheating for this new engine, (p1), will be no higher than the proportion of engine failures due to overheating of the old engines, (p2). To test this statement, NASCAR took a random sample of 185 of the new racecar engines and 150 of the old engines. They found that 22 of the new racecar engines and 11 of the old engines failed due to...
A salesman for a new manufacturer of cellular phones claims not only that they cost the retailer less but also that the percentage of defective cellular phones found among his products, ( p1 ), will be no higher than the percentage of defectives found in a competitor's line, ( p2 ). To test this statement, the retailer took a random sample of 210 of the salesman's cellular phones and 175 of the competitor's cellular phones. The retailer found that 24 of...
An engineer designed a valve that will regulate water pressure on an automobile engine. The engineer designed the valve such that it would produce a mean pressure of 6.66.6 pounds/square inch. The valve was tested on 120120 engines and the mean pressure was 6.86.8 pounds/square inch. Assume the variance is known to be 1.001.00. Is there evidence at the 0.050.05 level that the valve performs above the specifications? Step 2 of 5: Enter the value of the z test statistic....
An engineer has designed a valve that will regulate water pressure on an automobile engine. The valve was tested on 210 engines and the mean pressure was 7.1 pounds/square inch (psi). Assume the population standard deviation is 0.6. If the valve was designed to produce a mean pressure of 7.0 psi, is there sufficient evidence at the 0.05 level that the valve performs above the specifications? Step 1 of 6: State the null and alternative hypotheses. Step 2 of 6:...
An engineer has designed a valve that will regulate water pressure on an automobile engine. The valve was tested on 210 engines and the mean pressure was 4.9 pounds/square inch (psi). Assume the population variance is 1.00. If the valve was designed to produce a mean pressure of 4.7 psi, is there sufficient evidence at the 0.1 level that the valve performs above the specifications? Step 1 of 6: State the null and alternative hypotheses. Step 2 of 6: Find...
A Gallup poll to survey the top concerns of Americans was conducted. Suppose that 743 women and 713 men were independently and randomly selected, and that 383 women and 282282 men chose the state of the economy as their biggest concern. Can we conclude that the proportion of women ( p1 ), choosing the state of the economy as their biggest concern, exceeds the proportion of men ( p2 )? Use a significance level of α=0.1 for the test. Step 1...
A Gallup poll to survey the top concerns of Americans was conducted. Suppose that 387 women and 359 men were independently and randomly selected, and that 241 women and 202 men chose the state of the economy as their biggest concern. Can we conclude that the proportion of women (p1), choosing the state of the economy as their biggest concern, exceeds the proportion of men (p2)? Use a significance level of α=0.01 for the test. Step 1 of 6: State the...