A random sample of n, = 135 individuals results in x, = 39 successes. An independent sample of n, = 145 individuals results in x, = 62 successes. Does this represent sufficient evidence to conclude that p,

An electrical firm manufactures light bulbs that have a length of life that is approximately normally distributed with a standard deviation of 35 hours. If a sample of 45 bulbs has an average life of 780 hours, find a 96% confidence interval for the population mean of all bulbs produced by this firm. Click here to view page 1 of the standard normal distribution table. Click here to view page 2 of the standard normal distribution table. Click here to view page 1 of the table of critical values of the t-distribution. Click here to view page 2 of the table of critical values of the t-distribution. |<µ<. (Round to the nearest integer as needed.) The confidence interval is

Compute the critical value z,a/2. that corresponds to a 86% level of confidence. Click here to view the standard normal distribution table (page 1). Click here to view the standard normal distribution table (page 2). Za/2 = (Round to two decimal places as needed.)

In a study to estimate the proportion of residents in a certain city and its suburbs who favor the construction of a nuclear power plant, it is found that 77 of 125 urban residents favor the construction while only 56 of 100 suburban residents are in favor. Is there a significant difference between the proportions of urban and suburban residents who favor construction of the nuclear plant? Make use of a P-value. Click here to view page 1 of the standard normal distribution table. Click here to view page 2 of the standard normal distribution table. Let urban residents correspond to population 1, let suburban residents correspond to population 2, and let a success be a resident who favors the construction of a nuclear power plant. Identify the null and alternative hypotheses. OA. Ho: P₁ P2 H₁: P₁ P2 D. Ho: P₁ P2 H₁: P₁ = P2 Find the test statistic. B. Ho: P₁ = P2 H₁: P₁ P2 E. Ho: P₁ = P2 H₁: P₁ P₂ (Round to two decimal places as needed.) C. Ho: P₁ P2 H₁: P₁ = P2 OF. Ho: P1 P2 H₁: P₁ = P2

The acceptable level for insect filth in a certain food item is 4 insect fragments (larvae, eggs, body parts, and so on) per 10 grams. A simple random sample of 60 ten-gram portions of the food item is obtained and results in a sample mean of x = 4.2 insect fragments per ten-gram portion. Complete parts (a) through (c) below. Click here to view the standard normal distribution table (page 1). Click here to view the standard normal distribution table (page 2). (a) Why is the sampling distribution of x approximately normal? OA. The sampling distribution is approximately normal because the population is normally distributed and the sample size is large enough. B. The sampling distribution is approximately normal because the sample size is large enough. O C. The sampling distribution is assumed to be approximately normal. O D. The sampling distribution is approximately normal because the popluation is normally distributed. (b) What is the mean and standard deviation of the sampling…

A random sample of size n = 13 obtained from a population that is normally distributed results in a sample mean of 44.8 and sample standard deviation 12.7. An independent sample of size n = 18 obtained from a population that is normally distributed results in a sample mean of 52.3 and sample standard deviation 15.6. Does this constitute sufficient evidence to conclude that the population means differ at the a = 0.01 level of significance? Click here to view the standard normal distribution table (page 1). Click here to view the standard normal distribution table (page 2). Click here to view the table of critical t-values. Click here to view the chi-square critical values table. The given situation is about a mean, u. Write the hypotheses for the test. Họ: P1= 42 H1: H1 # 42 Calculate the test statistic. (Round to two decimal places as needed.)

Recall that if the sample proportion of defective cartridges is more than 0.02, the entire shipment will be returned to the vendor. We have been asked to determine the probability that a shipment will be returned if the true proportion of defective cartridges in the shipment is 0.06. This means we will find the area in the right tail of the standard normal distribution above the z-score of -2.55. Recall that n = 230, p = 0.02, and p = 0.06. Use the appropriate table in Appendix A or technology to find the probability. (Round your answer to four decimal places.) P(Returned) = P(p > 0.02) = P(z > -2.55) 0.9957 The approximate probability that a shipment will be,returned. if the true proportion of defective cartridges in the shipment is 0.06, rounded to four decimal places, is Enter a number.

In a random sample of 36 criminals convicted of a certain crime, it was determined that the mean length of sentencing was 54 months, with a standard deviation of 13 months. Construct and interpret a 90% confidence interval for the mean length of sentencing for this crime. Click here to view the standard normal distribution table (page 1). Click here to view the standard normal distribution table (page 2). Click here to view the table of critical t-values. Select the correct choice below and fill in the answer boxes to complete your choice. (Use ascending order. Round to one decimal place as needed.) O A. There is a 90% probability that the mean length of sentencing for the crime is between and months. O B. We can be 90% confident that the mean length of sentencing for the crime is between and months. O C. 90% of the sentences for the crime are between and months.

A random sample of 1009 adults in a certain large country was asked "Do you pretty much think televisions are a necessity or a luxury you could do without? Of the 1009 adults surveyed, 525 indicated that televisions are a luxury they could do without. Complete parts (a) through (d) below. Click here to view the standard normal distribution table (page 1). Click here to view the standard normal distribution table (page 2) BECCHE (a) Obtain a point estimate for the population proportion of adults in the country who believe that televisions are a luxury they could do without. (Round to three decimal places as needed.) (b) Verify that the requirements for constructing a confidence interval about p are satisfied. The sample Ya simple random sample, the value of is which is 10, and the less than or equal to 5% of the (Round to three decimal places as needed.) (c) Construct and interpret a 95% confidence interval for the population proportion of adults in the country who believe that…

In a survey, 34% of the respondents stated that they talk to their pets on the telephone. A veterinarian believed this result to be too high, so he randomly selected 210 pet owners and discovered that 70 of them spoke to their pet on the telephone. Does the veterinarian have a right to be skeptical? Use the a = 0.05 level of significance. Click here to view the standard normal distribution table (page 1). Click here to view the standard normal distribution table (page 2). Because npo (1- Po): V 10, the sample size is V 5% of the population size, and the sample the requirements for testing the hypothesis satisfied. (Round to one decimal place as needed.) What are the null and alternative hypotheses? versus H: Ho: (Type integers or decimals. Do not round.) Determine the test statistic, Zo Z0 = (Round to two decimal places as needed.) Determine the critical value(s). Select the correct choice below and fill in the answer box to complete your choice. (Round to two decimal places as…