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Problem 7-28 A student selects his answers on a true/false examination by tossing a coin (so...

Problem 7-28 A student selects his answers on a true/false examination by tossing a coin (so that any particular answer has a .50 probability of being correct). He must answer at least 70% correctly in order to pass. Find his probability of passing when the number of questions is

(a) 10 Pr=

(b) 20 Pr=

(c) 50 Pr=

(d) 100 Pr=

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