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1)Test scores are normally distributed with µ = 65 and σ = 12. What is the...

1)Test scores are normally distributed with µ = 65 and σ = 12. What is the probability of a score above 50?.

2)Grades should be distributed as follows: 15% A, 20% B, 30% C, 20% D, and 15% F. If a class of 50 has 7 A’s, 15 B’s, 10 C’s, 15 D’s, and 3 F’s, is there statistically significant evidence that this class does not fit the ideal distribution?

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