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According to the article "Are Babies Normal?" by Traci Clemons and Marcello Pagano published in The American Statistician, Vol. 53, No. 4, pp. 298-302, the birth weights of babies are normally distributed with a mean of 3388 grams and a standard deviation of 595 grams.
1.What is the probability that a randomly selected baby weighs between 3000 grams and 3500 grams? Round your answer to 4 decimal places.
2.What is the probability that the average weight of 24 randomly selected
Researcher is using data for a sample of 10 observations to estimate the relation
between consumption expenditure and income. Preliminary analysis of the sample data
produces the following data.
∑xy = 700 , 1000 2 ∑x = , ∑X = 100
∑Y = 200
Where i x Xi X
__
= − and
__
y = Yi − Y
a. Use the above information to compute OLS estimates of the intercept and slope
coefficients and interpret the result
b. Calculate the variance of the slope parameter
c. Compute the value R
2
(coefficient of determination) and interpret the result
d. Compute 95% confidence interval for the slope parameter
e. Test the significance of the slope parameter at 5% level of confidence using t-test
Emily and Andy each go to a hardware store to buy wire. The table shows the cost y in dollars for x inches of the wire they need. Emily needs 22 feet of the wire. Andy needs 13 yards of the wire. How much will each of them spend for wire?
The crumb and Custard bakery makes cakes and pies. The main ingredients are flour and sugar. The following linear programming model has been developed for determining the number of cakes and pies (x1 and x2 to produce each day to maximize profit.
Max Z=x1 + 5x2
Subject to:
8x1+10x2< 25(flour, lb)
2x1+4x2< 16(sugar, lb)
x1< 5(demand for cakes)
x1,x2 >0
Solve this model using simplex method.
Suppose that the four inspectors at a film factory are supposed to stamp the expiration date on each package of film at the end of the assembly line. John, who stamps 20% of the packages, fails to stamp the expiration date once in every 200 packages; Tom, who stamps 60% of the packages, fails to stamp the expiration date once in every 100 packages; Jeff, who stamps 15% of the packages, fails to stamp the expiration date once in every 90 packages; and Pat, who stamps 5% of the packages, fails to stamp the expiration date once in every 200 packages. If a customer complains that her package of film does not show the expiration date, what is the probability that it was inspected by John?
4. A soft-drink machine is regulated so that it discharges an average of 200 mls per cup. If the amount of drink is normally distributed with a standard deviation equal to 15 mls. Below what value do we get the smallest 30% of the cups?
(D² +40D'² +3D' )Z=ycos x
(D^ 2 -40D' +4D'^2)Z=e^ (2x+y)
(D^ 2 -40D' +4D'^2)2=e^ (2x+y)
A.) First sample has n=3 and M=8. Second sample has n=5 and M=6. What is the weighted mean?
B.) First sample has n=10 and M=12. Second sample has n=4 and M=7. What is the weighted mean?
Also do you mind showing me the formula how to find the weighted mean?
