Answer:
-2.6
Step-by-step explanation:
10.9 + (-15.6) becomes 10.9 - 15.6 which equals -4.7. The last step is to add the 2.1 to the -4.7: -4.7 + 2.1 = -2.6
Therefore the answer is -2.6
Answer:
The 95% confidence interval for the percentage of all boards in this shipment that fall outside the specification is (1.8%, 6.2%).
Step-by-step explanation:
In a random sample of 300 boards the number of boards that fall outside the specification is 12.
Compute the sample proportion of boards that fall outside the specification in this sample as follows:

The (1 - <em>α</em>)% confidence interval for population proportion <em>p</em> is:

The critical value of <em>z</em> for 95% confidence level is,

*Use a <em>z</em>-table.
Compute the 95% confidence interval for the proportion of all boards in this shipment that fall outside the specification as follows:

Thus, the 95% confidence interval for the proportion of all boards in this shipment that fall outside the specification is (1.8%, 6.2%).
So to solve problems like these you can work out each equation by substituting the x and y with the coords from the vertex (2,-4) and which ever one is true is the corresponding equation.
Lets try the first one
A) y = 2( x-2)^2-4 this would become
-4 = 2(2-2)^2-4 we solve this and get
-4 = 2(0)-4
-4 = -4
so it seems like A is the correct answer, of course we'd wanna check out the other answers just to be sure.
Lets try one and do C
C) -2 = 2(-4-2)^2+2
-2 = 2(-8)^2+2
-2 = 130
These aren't equal so this can't be our equation
So you can also do one more just to be super sure you have the right answer but I think A is the correct one :)
Answer:
$66.50, and you saved $28.50