The manager of a restaurant plans to survey a random sample of customers to estimate the proportion of customers who would return within a week if given a coupon for a free dessert to use on their next visit. A similar coupon was given last year, and 30 percent of the customers who were given the coupon returned within a week. The manager will use the observed proportion from last year as a preliminary estimate of the population proportion and wants the margin of error to be at most 0.04 at a 90 percent level of confidence. Of the following, which is the least number of customers who should be surveyed such that the estimate of the margin of error of the 90 percent confidence interval will be no greater than 0.04? (A) (B D 15 260 310 370 610

In a survey of 1150 adult males, 805 said they use the Internet. In a survey of 1050 females, 746 said they use the Internet. At a = 0.05, can you reject the claim that the proportion of Internet users are the same for both groups?

Suppose that 35% of all adults in a population would say “good” and 65% would say “bad” if they were asked how they view the state of the economy. An opinion poll asks this question of an SRS of 1000 adults from the population. In repeated samples, the sample proportion  who say “good” would follow a normal distribution, with the mean having a value of

According to the US Census Bureau in 2021, 23% of children under 18 live with only one parent. Melissa McCall wishes to see if this is a reasonable percentage for the children in Beacon Hills, California. She takes a random sample of 180 children under 18 for the study and finds that 52 live with only one parent. Test at a = 0.05. Show all seven steps

In this problem, assume that the distribution of differences is approximately normal. Note: For degrees of freedom d.f. not in the Student's t table, use the closest d.f. that is smaller. In some situations, this choice of d.f. may increase the P-value by a small amount and therefore produce a slightly more "conservative" answer.Do professional golfers play better in their last round? Let row B represent the score in the fourth (and final) round, and let row A represent the score in the first round of a professional golf tournament. A random sample of finalists in the British Open gave the following data for their first and last rounds in the tournament.

You plan to conduct a survey to estimate the percentage of adults who have had chickenpox. Find the number of people who must be surveyed if you want to be 93% confident that the sample percentage is within three percentage points of the true percentage for the population of all adults.   Assume that nothing is known about the prevalence of chickenpox.

You would like to estimate the proportion of all residents in favor of a new law with 98% confidence.  It is initially believed that 30% of all residents will be in favor of the new law.  Using this information, compute the smallest number of residents that must be sampled in order for the estimate to be within 6% of the true proportion.

A department store will place a sale item in a special display for a one-day sale. Previous experience suggests that 50 percent of all customers who pass such a special display will purchase the item. If 1,592 customers will pass the display on the day of the sale, and if a one-item-per-customer limit is placed on the sale item, how many units of the sale item should the store stock in order to have at most a 1 percent chance of running short of the item on the day of the sale? Assume here that customers make independent purchase decisions.

I need the right answers to b, c, & d.

In order to estimate attendance at a music festival, management counts the number of people entering the admissions gate in a 30- minute sample time. Management assumes that there is a steady stream of people entering the festival for the 10 hours that the admissions gate is open. At a particular music festival, 2,250 people were counted entering the gate in a 30- minute sample time. What was the estimated attendance at this festival?