Answer:
The 99% confidence interval would be given by (0.286;0.562)
Step-by-step explanation:
Information given:
represent the families owned at least one DVD player
represent the total number of families
represent the estimated proportion of families owned at least one DVD player
In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by 
and 
. And the critical value would be given by:
The confidence interval for the mean is given by the following formula:
If we replace the values obtained we got:
The 99% confidence interval would be given by (0.286;0.562)
Answer:
We need to find the value of b to make 8b - 27 be equal to 5, so:
8b - 27 = 5
We solve the equation:
8b = 5 + 27
8b = 32
We divide both sides by 8:
b = 32/8 = 4
So now, we know that b=4, and we can verify:
8*4 - 27 = 5
32 - 27 = 5 TRUE
I don’t know if that 2 and 1/4 or 21/4 so I’ll do both.
2 and 1/4 is = 9/4
21/4 is = 5 and 1/4
Answer:
x is equal to negative one, and y is equal to negative four.
Step-by-step explanation:
You can do this by solving one of the equations by either x or y, then substituting it into the other. Let's solve the second one for y:
Now we'll substitute that into the first equation:
So we now know that x is equal to -1. We can simply substitute that into one of the original equations to find y:
We now know that x is equal to -1, and y is equal to -4. We can also check our answer by plugging that -4 into the other equation, and see if we still get -1:
So we know that our answer is correct.
Answer: the Second one
Step-by-step explanation:
Hope this helps you
