1) The Department of Finance provided the following information regarding the new retail jobs created in a sample of 5 cities in 2009. The average number of new jobs created per city estimated to be 3320. We want to determine whether there has been a significant decrease in the average number of jobs created. State the null and the alternative hypotheses
| A) Ho: >4150 Ha: <4150 |
| B) Ho: >3320 Ha: <3320 |
| C) Ho: 3320 Ha: <3320 |
| D) Ho: 4150 Ha: <4150 |
2)A researcher wants to determine if the percentage of people who recycle newspapers is significantly different than 14.2%. In a survey of 900 people, 133 do. The p-value of the test is 61.7%.
3)Weekly average sales data at a retail store captured after an extensive marketing campaign is as follows:
| $4,666 |
| $6,700 |
| $4,500 |
| $5,550 |
| $4,768 |
| $4,950 |
| $5,225 |
The average sales at this store before the marketing campaign was $6,000 per week. Does the sample data collected after the marketing campaign indicate that the new marketing campaign had indeed increased the weekly sales? Use a 5% significance level
| a) The sample size (n=6) is too small to test this hypothesis |
| b) There is no strong evidence that the weekly average sales increased as a result of the marketing campaign as the the p-value is greater than the level of significance |
| c)The p-value is 0.0615, greater then the level of significance and therefore not evidence for increased sales |
d)A larger sample size is needed to test this hypothesis4)An addictions researcher wanted to determine if the average amount per week that people spend on lottery tickets has significantly changed from $9.42. In a survey of 750 people, the average was $10.52 with a standard deviation of $3.67. What is the value of the t score? | a) 8.2084 | | b) 7.6284 | | c) -7.6284 | | d) -8.2084 | |
5) Statistics Canada conducted a survey to assess the economic benefits of 2010 Winter Olympics on Vancouver. Of the 2500 random sample surveyed, 2250 of the respondents were optimistic about the economic benefits. Use a 99% confidence interval, estimate the proportion of all the respondents who were optimistic about the economic benefits. What is the interval value for the upper limit?
| a) 0.950 |
| b)0.915 |
| c)2.576 |
| d)0.015 |
6)A researcher wanted to estimate the percentage of people who read a certain newspaper. In a survey, the percentage of respondents who read the paper is 28.125%. When constructing a 95% confidence interval of the actual percentage of people who read the newspaper, the half-width is 0.110154255. What was the sample size?
7)A focus group of 16 companies was asked to estimate the annual amount spent on staff training. For this group, the average was $1,247 with a standard deviation of $313. If we construct a 99% confidence interval of the average amount spent per year by companies on staff training, what is the upper limit of the confidence interval, rounding to the nearest dollar?
| a) $1,426 |
| b) $1,478 |
| c) $1,475 |
| d) $1,384 |
8)A researcher wants to estimate the average amount of time that people spend to get to work. Based on previous data, the travel times are normally distributed with a mean of 25.2 minutes and standard deviation of 5.4 minutes. What is the required sample size, if the researcher wants to be accurate to within 0.5 minutes at a 95% level of confidence?
| a) 774 |
| b) 316 |
| c) 632 |
| d) 449 |
