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,




Answer: 7 3/4
Step-by-step explanation:
3 1/4 + 4 2/4 = 7 3/4
700/12 equals 58 and 1/3.
120% of 12 is 14.4.I got this by doing this:
12/x=100/120
<span>(12/x)*x=(100/120)*x - </span>we multiply both sides of the equation by x
<span>12=0.833333333333*x - </span>we divide both sides of the equation by (0.833333333333) to get x
<span>12/0.833333333333=x </span>
<span>14.4=x </span>
<span>x=14.4</span>