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In: Statistics and Probability

Consider the variable x = time required for a college student to complete a standardized exam....

Consider the variable x = time required for a college student to complete a standardized exam. Suppose that for the population of students at a particular university, the distribution of x is well approximated by a normal curve with mean 55 minutes and standard deviation 5 minutes. (Use a table or technology.)

(a)

If 60 minutes is allowed for the exam, what proportion of students at this university would be unable to finish in the allotted time? (Round your answer to four decimal places.)

(b)

How much time (in minutes) should be allowed for the exam if you wanted 95% of the students taking the test to be able to finish in the allotted time? (Round your answer to one decimal place.)

min

(c)

How much time (in minutes) is required for the fastest 20% of all students to complete the exam? (Round your answer to one decimal place.)

min

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