math stisctic 255

C 1. According to the empirical rule, approximately what range would you expect 95% of data to fall? a. Within 5% of your mean b. Within 1 standard deviation of your mean Within 2 standard deviations of your mean Within 3 standard deviations of your mean Q 2. How does the mean of a positively skewed population compare to the median of the same population? The mean is higher. b. The mean is lower. C. The mean is the same. d. There is not enough information to determine a comparison. 3. Which of the below values for a coefficient of determination (r) represents the strongest linear correlation between two variables? a. -.977 b. .643 c. .0962 d. 1.41 4. A study finds that 70% of the population talk to their mother at least once a week. If you ask 240 people at random, how many of them would you expect talk to their mother once a week? a. 70 b. 124 C. 168 d. 170 5. A research company wants to take a poll of the views of Americans. They randomly select a social security number, then contact Americans by social security numbers that are found by adding 090-09-0900 to the preceding selected number until they get a total of 1500 responses. This is an example of: a. systematic sampling b. convenience sampling c. cluster sampling d. random sampling