Answer:
a. n= 47
b. n= 128
Step-by-step explanation:
Hello!
The objective of this experiment is to test if the new catalyst, XA-100, increases the mean hourly yield of a chemical process, that is known to be μ=750 (pounds per hour) with the current process.
You need to calculate the sample size to estimate the population with determined error margins.
To do so, since you have no population information, only that it is approximately normal distributed, you'll use the Student t statistic to get the sample size.
The formula of the margin of error (d) is:
d= 
* (
)
I've cleared the sample size of the formula
You need a sample size for the t-Student value and a standard deviation, that's why the information of a pilot study with n=5 and S= 19.62 is given.
a)
95% CI
d= 8 pounds
n= 46.35 ≅ 47
b)
99% CI
d= 5 pounds
n= 127.49 ≅ 128
I hope it helps!
Answer:
45 
Step-by-step explanation:
Multiply 9 · 10 = 90 then divided by 2 = 45
The mean is equal for Group A and Group B.
<h2>Given </h2>
Two groups of students were asked how far they lived from their school.
The table shows the distances in miles:
Group A (distance in miles) 1 1.5 3.03 3.2 2.8 1.5 1.8 2.5 2.2
Group B (distance in miles) 2 2.5 3.23 1.3 1.8 2.4 3 1.5 1.8
<h3>What is mean?</h3>
The mean of any data set or observation is equal to the sum of all the observations and divided by the number of observations.
The formula used to calculate the mean is;
The mean of group A is;
The mean of group B is;
Hence, the mean is equal for Group A and Group B.
To know more about Mean click the link given below.
brainly.com/question/12513463
Use pemdas : so do parenthesis first 15-8, then multiply the answer by 6. OR u can use distributive property & multiply 6 by 15 & 8
