harryabel62
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A health food cooperative markets free-range eggs. Eggs weighing less than 48g are graded small, those weighing more than 59g are graded large and the rest are graded medium.

The weight of an egg from a particular supplier is normally distributed with mean 52g and standard deviation 4g.
Find:
(a) The proportion of eggs graded small,
(b) The proportion of eggs graded medium,
(c) The median weight of the eggs graded large.
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username2130115
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Write the probabilities down then change the weights to a Z value
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harryabel62
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are my answers right?
A)0.1587
B)0.0401
c) dont know?
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username2130115
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(Original post by harryabel62)
are my answers right?
A)0.1587
B)0.0401
c) dont know?
post your workings. remember any random variable that has a normal distribution has the property mean = median = P(Z < 0) = 0.5
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harryabel62
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a) (48-51)/4 = -1
z=0.8413
1-0.8413= 0.1587

C)0.0401/2 = 0.02005
rounded up to 0.0201
got .58 in the inverse phi table and did
x = 4(0.58)+59 and got 61.32g
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H.b9
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A) •P(52-4<x<52+4) = .6827
•P(x<52)=.50
•P(48<x<52)=.6827/2=.34135

Answer:
P(x<48)= .50-.34135=.15865

For B I used my graphic calculator which then gave me an answer of approx. .80


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