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2. [-I1 Points] DETAILS WANEFMAC?r 9.4.013. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Calculate the standard deviation a of)! for the probability distribution. (Round your answer to two decimal places.) 3. [f1 Points] DETAILS WANEFMAC? 9.4.014. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Calculate the standard deviation 0 ofX for the probability distribution. (Round your answer to two decimal places.) EIolT o | m We so P(X=x) I 0.3 l 0.3 I 0.2 | 0.1 | 0 0.1 Need Help? _ 4. [I1 Points] DETAILS WANEFMAC? 9.4.021. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Calculate the expected valuer the variance, and the standard deviation of the given random variable X. (Round all answers to two decimal places.) X is the number of red marbles that Suzan has in her hand after she selects five marbles from a bag containing five red marbles and two green ones. expected value [:] standard deviation [j ~eea Help? 5. [0.2\" Points] DETAILS PREVIOUS ANSWERS WANEFMAC? 9.4.025. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Popularlty Ratings In your bid to be elected class representative, you have your election committee survey ve randomly chosen students in your class and ask them to rank you on a scale of 0-10. Your rankings are 1, 5, 8, 2, 3. (a) Find the sample mean and standard deviation. (Round your answers to two decimal places.) sample mean C] standard deviation S (b) Assuming the sample mean and standard deviation are indicative of the class as a wholer in what range does the empirical rule predict that approximately 68% of the class will rank you? I:H:ll what other assumptions must we make to use the rule? O The population distribution is symmetric, but not bell-shaped. O The population distribution is bell-shaped and symmetric. O The population distribution is bell-shaped, but not symmetric. O The population distribution is neither bell-shaped nor symmetric. ~I