
now, what's the leftover? well, 3/4 of the last one, namely 3/4 of 2/3, what is 3/4 of 2/3 anyway? well, is just their product,
Answer:
The 90% confidence interval for the average monthly residential water usage for all households in this city is between 4401.3 gallons and 4598.7 gallons.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so 
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 4500 - 98.7 = 4401.3 gallons
The upper end of the interval is the sample mean added to M. So it is 4500 + 98.7 = 4598.7 gallons
The 90% confidence interval for the average monthly residential water usage for all households in this city is between 4401.3 gallons and 4598.7 gallons.
Use one of the many Trigonometric ratios to solve for the missing angle and then use Pythagorean theorem to solve for the missing side.
These things can be done in any order.
The answer would be B because it crosses the X axis closer to the 0,0 than the original line
Answer: Ali would need to drive 350 miles for the two plans to cost the same.
Step-by-step explanation:
This question can be solved by creating two equations using the information supplied in the question and then solving these simultaneously.
Let the cost be C.
Let the number of miles be M.
Let the initial payment be i.
Let the rate per mile driven be R.
Plan 1:
C = i+R×M
C = 70+0.60M ... equation 1
Plan 2:
C = i+R×M
C = 0+0.80M
C = 0.80M ...equation 2
Substituting equation 2 into equation 1:
0.80M = 70+0.60M
0.80-0.60M = 70
0.20M = 70
M = 70/0.20
M = 350 miles