First we need to have same units before comparing them. That is, either both of them are in cm or both of them are in mm. So if we need to convert 12.5 cm to mm, we know that 1 cm =10 mm. So we have to find out how many mm are in 12.5 cm. And let 12.5 cm =x mm. So to find the value of x , we set a proportion and solve for x. That is
The units cancel out and we do cross multiplication. That is
x=125
So 12.5 cm =125 mm. Therefore the correct proportion is C.
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,