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Need help with normal distribution questions

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1. P = 0.3 ==> z = 0.5244 = (μ - 32)/σ . P = 0.85 ==> z = 1.0364 = (44 - μ)/σ, 44 > μ > 32. Some calculators give negative values for z scores in x < 0. Just make sure the signs match on both sides (positive = positive, or negative = negative). 

μ = 36.0, σ = 7.69

2. a) P = 0.1057 ==> z = 1.25 = (5 - 4) / σ, σ = 1/1.25 = 0.8

b) Find probability of X from 4.5 to 5.5. You can just directly plug in calculator: 0.47

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