SOLUTION: the incubation time for rhode island red chicks is normally distributed with a mean of 21 days and standard deviation of approx. 1 day look at figure 7-3 and answer the following q

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Question 151420: the incubation time for rhode island red chicks is normally distributed with a mean of 21 days and standard deviation of approx. 1 day look at figure 7-3 and answer the following questions. if 1000 eggs are being incubated how many chicks do we expect will hatch
a) in 19 to 23 days
b) in 20 to 22 days
c) in 21 days or fewer
d)in 18 to 24 days? ( assume all eggs eventually hatch)
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
the incubation time for rhode island red chicks is normally distributed with a mean of 21 days and standard deviation of approx. 1 day
look at figure 7-3 and answer the following questions.
if 1000 eggs are being*incubated how many chicks do we expect will hatch
a) in 19 to 23 days
Find the probability the incubation time is between 19 and 23 days.
You need to find the z-values of 19 and of 23
z(19) = (19-21)/1 = -2
z(23) = (23-21)/1 = 2
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Then P(19 < x < 23) = P(-2 < z < 2) = 0.95
Ans: 0.95*1000 = 950 eggs
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b) in 20 to 22 days
You need to find the z-values of 20 and of 22
z(20) = (20-21)/1 = -1
P(22) = (22-21)/1 = 1
Then P(20 < x < 22) = P(-1 < z < 1) = 0.68
Ans: 0.68*1000 = 680 eggs
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c) in 21 days or fewer
Find the z-values of 0 and 21
z(0) = (0-21)/1 = -21
z(21) = (21-21)/1 = 0
P(0 < x < 21) = P(-21 < z < 0) = 0.50
Ans: 0.50*1000 = 500
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d)in 18 to 24 days? ( assume all eggs eventually hatch)
P(18 < x < 24) = 0.9973
Ans: 0.9973*1000 = 997 eggs
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Cheers,
Stan H.