A choice answer exam (4 choices per question) has 10 questions. A student who has not studied at all randomly answers all questions independently. a) What grade can he expect? With what standard deviation? b) What is the probability that he has exactly 7 correct answers? c) What is the probability that he obtains at least 60% on this exam?

A choice answer exam (4 choices per question) has 10 questions. A student who has not studied at all randomly answers all questions independently. a) What grade can he expect? With what standard deviation? b) What is the probability that he has exactly 7 correct answers? c) What is the probability that he obtains at least 60% on this exam?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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