Suppose your grade in a course depends on 10 weekly quizzes. Each quiz has ten yes/no...

  

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Suppose your grade in a course depends on 10 weekly quizzes. Each quiz has ten yes/no questions, each worth 1 point. The scoring has no partial credit. Your performance is a model of consistency: on each 1 point question, you get the right answer with probability p = 0.8, independent of the outcome on any other question. Thus your score X, on quiz i is between 0 and 10 Your average score per question is X = Σi, X/100. The course has K online surveys. For each survey you take, you get a 10 point bonus credit. If you take k surveys, your modified semester average is 10k+ 510 Yk 10k+100 If you take k surveys, Y is used to determine your course grade using simple letter grades without any curve: A: Yk ≥ 0.9 B:0.8Y<0.9 C:0.7 ≤Y < 0.8 D:0.6 Y <0.7 F:Y, <0.6 Let Q(x) denote the tail distribution function of the standard normal distribution and (x) denote the CDF of the standard normal distribution. Please select the true statements among the following 10 statements. The PMF of X; Is Px, (2) = (10) (0.8)-( 20 E[100X] = 80 Var[100X] = 16 (0.8) (0.2) ¹0- If there is no survey (K = 0), the probability P[A] that you receive an A grade is Q(2.5). If there is no survey (K = 0), the probability P[F] that you receive an F grade is 1 - Þ(5). If you take k surveys, the probability P[A] that you receive an A grade is Q (2.5 -0.25k). If you take k surveys, the probability P[F] that you receive an F grade is 1 - Þ(5 + k). 90 Let Z = 2 X₁, the PMF is P₂ (z) = ( 20 ) (0.8) (0.2) - if X₁ = 10, the probability that your average score is X = 0.9 is P₂ (80) = (30) (0.8) 5⁰ (0.2)¹0, where Z = X₁. 90 80 i=2 If you take 2 surveys, E[Y] = 5/6. Act Go to Suppose your grade in a course depends on 10 weekly quizzes. Each quiz has ten yes/no questions, each worth 1 point. The scoring has no partial credit. Your performance is a model of consistency: on each 1 point question, you get the right answer with probability p = 0.8, independent of the outcome on any other question. Thus your score X, on quiz i is between 0 and 10 Your average score per question is X = Σi, X/100. The course has K online surveys. For each survey you take, you get a 10 point bonus credit. If you take k surveys, your modified semester average is 10k+ 510 Yk 10k+100 If you take k surveys, Y is used to determine your course grade using simple letter grades without any curve: A: Yk ≥ 0.9 B:0.8Y<0.9 C:0.7 ≤Y < 0.8 D:0.6 Y <0.7 F:Y, <0.6 Let Q(x) denote the tail distribution function of the standard normal distribution and (x) denote the CDF of the standard normal distribution. Please select the true statements among the following 10 statements. The PMF of X; Is Px, (2) = (10) (0.8)-( 20 E[100X] = 80 Var[100X] = 16 (0.8) (0.2) ¹0- If there is no survey (K = 0), the probability P[A] that you receive an A grade is Q(2.5). If there is no survey (K = 0), the probability P[F] that you receive an F grade is 1 - Þ(5). If you take k surveys, the probability P[A] that you receive an A grade is Q (2.5 -0.25k). If you take k surveys, the probability P[F] that you receive an F grade is 1 - Þ(5 + k). 90 Let Z = 2 X₁, the PMF is P₂ (z) = ( 20 ) (0.8) (0.2) - if X₁ = 10, the probability that your average score is X = 0.9 is P₂ (80) = (30) (0.8) 5⁰ (0.2)¹0, where Z = X₁. 90 80 i=2 If you take 2 surveys, E[Y] = 5/6. Act Go to