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1. Which of the following can be classified as Discrete and Quantitative data? The acceleration of your car as you drive to school The different colors of the eyes of your classmates The number of students in your school The height of all people in your neighborhood 2. What type of distribution is described by the following information? Mean=56 Median=58.1 Mode= 63 Negatively skewed Symmetrical Bimodal Positively skewed 3. In a standardized IQ test, the mean score is 100 and the standard deviation is 15. According to the Empirical rule, 95% of all those who took the test should have scores between 70-130 85-115 55-145 100-130 4. There are 10 colored balls in a box (5 red, 3 blue, 2 green). What is the probability of picking out a red ball and then a blue ball (if the red ball is not replaced)? 1/6 1/2 3/20 4/5 5. If I go into an ice cream parlor and I have the choice of having one of 10 different flavors, with one of 5 different toppings and one of 3 different types of cones, how many times can I come back to this place and get a different ice cream cone combination? 150 times 6. The Sarasota Police Dept collected data on the number of car accidents (x) that occur each day on a certain stretch of route 41. From this data, they derived the probability distribution shown in the table below x P(x) 0 0.80 1 0.15 2 0.05 What is the expected mean of accidents that occur each day Expected mean = (0)(0.8) + (1)(0.15) + (2)(0.05) = 0.25 7. What is meant by the 95% confidence interval of the mean? That 95% of my sample is OK to do more tests That I am 95% confident that the confidence interval will contain the parameter being estimated That 5% of my sample is not ok That I am 95% sure that the population mean is 95. 8. Consider a binomial random variable where the number of trials is 12 and the probability of success on each trial is 0.25. Find the mean and the standard deviation of this random variable. Mean = n * p = 12 * (1/4) = 3 Standard deviation = √(n*p*q) = √(12*1/4*3/4) = √2.25 = 1.5 9. If my p-value = 0.322 and my significant level is 0.05 then My null hypothesis is rejected and I must accept the alternative hypothesis My Null Hypothesis is not rejected My alternative hypothesis becomes the new null hypothesis I cannot make a decision until I know my sample size 10. Suppose I am using the t-distribution to estimate or test the mean of a sample from a single population. If the sample size is 25, then the degrees of freedom are? 26 25 24 30