Answer:
confidence interval = ( -0.38 , 0.08 )
Step-by-step explanation:
Given data :
n1 = 55 , n2 = 60 ,
Let P1 ( proportion of SUV sales at store A ) = 30 / 55 = 0.55
P2 ( sample proportion of SUV sales at store B ) = 42/60 = 0.70
The Z-value at 99% confidence Interval = 2.58
<u>Determine the 99% confidence interval for difference in proportion</u>
applying the formula below
( P1 - P2 ) ± Z (
Input values above into equation
confidence interval = ( -0.38 , 0.08 )
Answer:
B
Step-by-step explanation:
One good way to look at this is to graph both polynomials, as shown in the picture. A tip to help graph is to factor it out and work from there. For example, in x²+14x+48, we can gather that (x+6)(x+8) is the same thing, and it is easier to then graph it. Similarly, for x²+12x+36, we can factor it out as (x+6)² .
When x²+12x+36 approaches 6, it is getting really close to 0, but it stays positive. When x²+14x+48 approaches 6 from the negative side, it is also getting close to 0, but it's negative. When x²+14x+48 approaches 6 from the positive side, it is positive.
Therefore, on the negative side, there is one positive and one negative (dividing a negative by a positive is negative, and a positive by a negative is also negative) , and on the positive side, there are two positives, forming one answer.The answer is therefore B
