Question 608257
A quart of parkers milk contains a mean of 39 grams of butterfat with a standard deviation of 2 grams. If the butterfat is normally distrubuted find the probability that the quart of this brand of milk chosen at random will contain 
A. 39-43 grams of butterfat 
z(39) = (39-39)/2 = 0
z(43) = (43-39)/2 = 2
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P(39<= x <=43) = P(0<= x <=2) = 0.4772
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B. 36-39 grams of butterfat
z(36) = (36-39)/2 = -3/2
z(39) = 0
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P(36<= x <=39) = P(-3/2<= z <=0) = 0.4332
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Cheers,
Stan H.
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