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Question 1 a) Find two values symmetric around a mean of 20 such that they include...

Question 1

a) Find two values symmetric around a mean of 20 such that they include an area equal to 0.75. (standard deviation = 5).

b) A professor grades his students on a normal distribution, with mean at 75 and standard deviation of 15. What percentage scored between 80 and 90?

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