Answer:
Step-by-step explanation:
Given : A new catalyst is being investigated for use in the production of a plastic chemical. Ten batches of the chemical are produced. The mean yield of the 10 batches is 72.5% and the standard deviation is 5.8%. Assume the yields are independent and approximately normally distributed.
To find : A 99% confidence interval for the mean yield when the new catalyst is used ?
Solution :
Let X be the yield of the batches.
We have given, n=10 , 
, s=5.8%
Since the size of the sample is small.
We will use the student's t statistic to construct a 995 confidence interval.
From the t-table with 9 degree of freedom for 
The 99% confidence interval is given by,
Choice b would be correct since the slope of the line is negative !
The value of the Z-score will be equal to 2.
<h3>What is Z-score?</h3>
The z score indicates how many standard deviations your score is from the mean.
At the mean position, the standard deviation is 0 now the z score is the measure of the data which is how far from the mean. So the given data is at two standard deviations to the right of the mean so the Z-Score will be 2.
Therefore the value of the Z-score will be equal to 2.
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Answer:
9
Step-by-step explanation:
To find the slope of a line, calculate the distance between points with a ratio of vertical to horizontal distance. This is done using the formula:
Here the points are (-7,-2) and (-6,7). Substitute and simplify.
Answer:
f = .39
Step-by-step explanation:
d (v) = 2.15 v^2 / (64.4 f)
v = 40
d = 138
substitute these in
138 = 2.15 (40)^2 / (64.4 *f)
simplify
138 = 2.15 (*1600) / (64.4 *f)
138 = 3440 / (64.4 *f)
multiply each side by 64.4f
138 * 64.4 f = 3440
8887.2 f = 3440
divide by 8887.2
8887.2 f /8887.2= 3440/8887.2
f=.38707
to the nearest hundredth
f = .39
