Step-by-step explanation:
Given - In selecting a sulfur concrete for roadway construction in regions that experience heavy frost, it is important that the chosen concrete has a low value of thermal conductivity in order to minimize subsequent damage due to changing temperatures. Suppose two types of concrete, a graded aggregate and a no-fines aggregate, are being considered for a certain road. The table below summarizes data on thermal conductivity from an experiment carried out to compare the two types of concrete.
Type ni xi si
Graded 42 0.486 0.187
No-fines 42 0.359 0.158
To find - a. Formulate the above in terms of a hypothesis testing problem.
b. Give the test statistic and its reference distribution (under the null hypothesis).
c. Report the p-value of the test statistic and use it to assess the evidence that this sample provides on the scientific question of difference in mean conductivity of the two materials at the 5% level of significance.
Proof -
a.)
Hypothesis testing problem :
H0 : There is significant difference between mean conductivity for the graded concrete and mean conductivity for the no fines concrete.
H1 : There is no significant difference between mean conductivity for the graded concrete and mean conductivity for the no fines concrete.
b)
Test statistic :




⇒Z(cal) = 3.3687
Z(tab) = 1.96
As Z (cal) > Z(tab)
So, we reject H0 at 5% Level of significance
p-value = 0.99962
Hence
There is significant difference in mean conductivity at the two materials.
So product means multiplication so -2*(x-6) > -18 so divide by -2 on both sides to get x-6<9 because when you multiply a negative the sign swaps directions and then add 6 to get x<15
These three roots are sufficient to enable us to form a 3rd degree polynomial:
f(x) = (x+4)(x-4)(x-2) = (x^2 - 16)(x-2) = x^3 - 2x^2 - 16x + 32 (answer)
Answer: 
<u>Simplify both sides of the equation</u>

<u>Subtract 5n from both sides</u>

<u>Subtract 15 from both sides</u>

Answer:
from my understanding the correct answer should be
Red is the most popular in the East than in the other regions
About 17% of the people in the Midwest have a gray car
White is the most popular in every region
Silver and black are equally popular in the East.
*** i hope im right sorry if this didnt help:/***