A set of final grades in an introductory probability class in section A is normal distributed...

A set of final grades in an introductory probability class in section A is normal distributed with mean 70 and standard deviation of 10 : G1 ~ N (70,100). a) what is probability that grade of randomly chosen student is 77 or less? b)what is probability that average grade of 9 randomly chosen students is 77 or less? c) only 2% of the students scored higher that what grade? d) A set of final grades in an introductory probability class in section B is normally distributed with mean 75 and unknown standard deviation σ : G2 ~ N (75, σ2). If probability that G2 ≤ 80 is 0.8159, I)what is the value of σ ? II) what is the probability that randomly chosen student from class A scores more than randomly chosen student from class B ?

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orchestra answered 1 year ago

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