A marketing firm wants to compare the proportion of those who say they are regular viewers of reality TV in the 20-29 year and 30-39 year age groups.  In a random sample of 150 people aged 20-29, 52 said they are regular viewers of reality TV.  In a random sample of 200 people aged 30-39, 53 said they are regular viewers of reality TV.  At the 0.05 level of significance test to determine if the proportion is the same in the two age groups.  Assume that the conditions to complete the hypothesis test are met.  1) What is the correct null and alternative hypothesis?  Choose from the options below.  [answer1]                                   a.     H0: 

A random sample of SMC math students are asked how much time (in minutes) they spend on math homework per day.  The responses are listed below.  Calculate the 95% confidence interval for the mean time an SMC math students spend on homework per day.  Assume that the conditions are met to calculate the interval.  Round the end points of the interval to one decimal place.  The units of the interval are minutes.  54     62     42     49     39     53     41     39     29     71  

You have been asked to evaluate the claims of a new diet company.  Their advertising says that the typical customer loses more than 3 pounds in a month.  A random sample of 10 customers is chosen and the number of pounds lost is recorded.  The data is recorded below, in pounds lost. You can assume that the conditions to calculate a confidence interval and to do a hypothesis test are met.    5.1     5.4     4.2     7.2     3.6     4.8     2.7     5.6     6.4     6.1 1) Find the mean, median and standard deviation of this data set.          mean = [mean]                standard deviation = [sd]               median = [med] 2) You can conclude that the data set is approximately normal because [because] 3) Find the 95% confidence interval estimate for the mean number of pounds lost per month on this diet plan.  [CI]  4) A hypothesis test at the 0.05 level of significance is to be done to test the claim that the mean weight loss is more than 3 pounds per month.          What are the null and alternative hypotheses?     Ho:  

Classify the following random variable according to whether it is discrete or continuous. The number of players on a football team. 

Identify the level of measurement (nominal, ordinal, interval, ratio) for each of the following variables.  a. Year of Birth  [answera] b. Type of Bird  [answerb] c. Volume of water in a Lake [answerc] d. Rating of a crossword puzzle (easy, medium, hard, expert)  [answerd]

The table below gives the results of a survey given to a random sample of credit card users living in the Los Angeles area.  They were asked their age group and whether or not they pay their credit card balance off in full each month.   Data table Pay off fully each month Do not pay off fully each month Age 20 to 29 years 74 51 Age 30 to 39 years 72 37 Age 40 to 49 years 81 25 Age 50 and older 92 26 Answer the following based on the information in this table.  If rounding is necessary, round to three decimal places.  If a credit card user is randomly selected, what is the probability that they are aged 30 to 39 and do not pay their bill fully each month?  [one] If a credit card user is randomly selected, what is the probability that they are aged 20 to 29 or do not pay off their bill fully each month?  [tw] If a person who does not pay off their bill each month is chosen, what is the probability that they are aged 50 and older? [three]

The table below gives the probability distribution of the number days that workers at a certain company have missed work in the last month.  Data Table Number of Days Missed (x) P(x) 0 0.45 1 0.29 2 0.21 3 ? 4 0.02 Use this table to answer the following. Complete the table by finding P(3).   [answera] Is the random variable, x, discrete or continuous?  [answerb] What is the most likely number of days missed by a worker at this company? If rounding is  necessary, round to two decimal places. [answerc] What is the expected number of days missed by a worker at this company  If rounding is necessary, round to two decimal places. [answerd]  What is the standard deviation in the number of days of work missed by a worker at this company?  If rounding is necessary, round to two decimal places. [answere] Which of the following interpretations of the expected value is correct? [exp]  

Determine whether the sampling is independent or dependent and whether the variable is qualitative or quantitative.  A psychologist wants to measure the effect of music on relaxation.  He random selects 75 volunteers and measures their stress level in silence and then again with the same volunteers the next day while music is playing.   The mean score without music is compared to the mean score with music.

Identify the level of measurement (nominal, ordinal, interval, ratio) for each of the following variables.  a. Temperature of a cup of coffee [cof] b. Height of a 6-year old in inches [hei] c. Color of a car [car] d. Size of a rental car: subcompact, compact, standard, full-size [size]

Which of the following will decrease the width of a confidence interval?