Simplest way to do this:
 number of books= 120
 percentage represented by 120= 100%
 increase current percent by 55%= 155%
: . 55% increase = original number of books * (155%)
                           = 120 * (155/100)
                           = 186
        
             
        
        
        
Part A
Answers:
Mean = 5.7
Standard Deviation = 0.046
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The mean is given to us, which was 5.7, so there's no need to do any work there.
To get the standard deviation of the sample distribution, we divide the given standard deviation s = 0.26 by the square root of the sample size n = 32
So, we get s/sqrt(n) = 0.26/sqrt(32) = 0.0459619 which rounds to 0.046
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Part B
The 95% confidence interval is roughly (3.73, 7.67)
The margin of error expression is z*s/sqrt(n)
The interpretation is that if we generated 100 confidence intervals, then roughly 95% of them will have the mean between 3.73 and 7.67
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At 95% confidence, the critical value is z = 1.96 approximately
ME = margin of error
ME = z*s/sqrt(n)
ME = 1.96*5.7/sqrt(32)
ME = 1.974949
The margin of error is roughly 1.974949
The lower and upper boundaries (L and U respectively) are:
L = xbar-ME
L = 5.7-1.974949
L = 3.725051
L = 3.73
and
U = xbar+ME
U = 5.7+1.974949
U = 7.674949
U = 7.67
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Part C
Confidence interval is (5.99, 6.21)
Margin of Error expression is z*s/sqrt(n)
If we generate 100 intervals, then roughly 95 of them will have the mean between 5.99 and 6.21. We are 95% confident that the mean is between those values.
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At 95% confidence, the critical value is z = 1.96 approximately
ME = margin of error
ME = z*s/sqrt(n)
ME = 1.96*0.34/sqrt(34)
ME = 0.114286657
The margin of error is roughly 0.114286657
L = lower limit
L = xbar-ME
L = 6.1-0.114286657
L = 5.985713343
L = 5.99
U = upper limit
U = xbar+ME
U = 6.1+0.114286657
U = 6.214286657
U = 6.21
        
             
        
        
        
Answer:
Sea level
Step-by-step explanation:
In geography, 'Elevation' is measured in relation to sea level, so sea level would be zero.
Thus, Chicago is 600 feet above sea level and Seely, California is 200 feet below sea level.
If there were nothing but flat land all the way from Seely to the ocean, sea water would come in and cover Seely. Fortunately for the people in Seely. California's coastal mountain range is between the town and the ocean, so that does not happen.
 
        
                    
             
        
        
        
If you were selling an items for $35.50 as the original price, but you give 30% off the item price then the result of it's cost would be: 
Sale / Discounted Price: $26.95
Then if you're wondering, you'll be saving this amount of money:
Amount Saved (Discount): $11.55
Hope this helps!