Answer:
The value is 
Step-by-step explanation:
From the question we are told that
The mean is 
The standard deviation is 
The safest water level is between 7.2 and 7.8
Generally the probability that the selected pool has a pH level that is not considered safe is mathematically represented as

Here

Generally 
So
=>
From the z-table the probability of (Z < -1.5) and ( Z <1.5) are

and

So
So

=> 
Answer:
(c) Observational Distribution
(d) Diet Choice
Step-by-step explanation:
Out of 1033 American adults interviewed in July 2018, 5% consider themselves to be vegetarian.
Since the poll observes the diet habit of the respondents, the cited 5% is part of the Observational distribution of whether the respondent is a vegetarian or not (which is the Diet Choice).
If on the other hand, the poll seeks to manipulate the conditions of the study, it would have been an experimental distribution.
Answer:
8 1/4
Step-by-step explanation:
20 2/4
-
12 3/4
__________
8 1/4
Answer:
D. The difference of the means is not significant because the re-randomizations show that it is within the range of what could happen by chance.
Step-by-step explanation:
The treatment group using System A reported a mean of 18.5 lost bags per day. The treatment group using System B reported a mean of 16.6 lost bags per day.
The best conclusion that can be made is - The difference of the means is not significant because the re-randomizations show that it is within the range of what could happen by chance.
As we know, in statistics, nothing happens by chance. So, this option is correct.
You haven't provided the choices, therefore, I cannot provide an exact answer. However, I will help you with the concept.
For an order pair to be a solution to a system of equations, it has to satisfy <u>BOTH</u> equations. If it satisfies only one equation of the system or satisfy neither of the equations, the, it is not a solutions
<u><em>Examples:</em></u>
<u>System 1:</u>
x = y + 1
2x + 3y = 7
Let's check (2,1)
2 = 1 + 1 ........> equation 1 is satisfied
2(2) + 3(1) = 7 ......> equation 2 is satisfied
<u>(2,1) is a solution to this system</u>
<u>System 2:</u>
y = x + 3
y = x - 1
Let's check (2,1):
1 ≠ 2 + 3 ........> equation 1 isn't satisfied
1 = 2 - 1 ..........> equation 2 is satisfied
<u>(2,1) isn't a solution to this system</u>
<u>System 3:</u>
2y = 9 - 3x
3x + 2y = 9
Let's ceck (2,1):
2(1) ≠ 9 - 3(2) ..........> equation 1 isn't satisfied
3(2) + 2(1) ≠ 9 .........> equation 2 isn't satisfied
<u>(2,1) isn't a solution to this system
</u>
<u><em>Based on the above,</em></u> all you have to do is substitute with (2,1) in the system you have and pick the one where both equations are satisfied
Hope this helps :)