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,
4136/8= 517
The others
7116/8=889.5
4309/8=538.625
9406/8=1175.75
Answer:if the notebooks cost 3.59 and pens cost 1.49, with x representing the notebooks and y representing the number of pens and an amount of $13, the inequality would be written as 3.59x+1.49y13
Step-by-step explanation:
Answer:
7.3% percentage of the bearings produced will not be acceptable.
Step-by-step explanation:
Consider the provided information.
Average diameter of the bearings it produces is .500 inches. A bearing is acceptable if its diameter is within .004 inches of this target value.
Let X is the normal random variable which represents the diameter of bearing.
Thus, 0.500-0.004<X<0.500+0.004
0.496<X<0.504
The bearings have normally distributed diameters with mean value .499 inches and standard deviation .002 inches.
Use the Z score formula: 
Therefore
Now use the standard normal table and determine the probability of that a ball bearing will be acceptable.
We need to find the percentage of the bearings produced will not be acceptable.
So subtract it from 1 as shown.
1-0.9270=0.073
Hence, 7.3% percentage of the bearings produced will not be acceptable.
