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.
Answer:
-5x^6-8x^2+6x+11
Step-by-step explanation:
(-5x^6+7x+1)-(8x^2+x-10)
Remove parentheses
-5x^6+7x+1-(8x^2+x-10)
-(8x^2+x-10)=-8x^2-x+10
-5x^6+7x+1-8x^2-x+10
Simplify
-5x^6-8x^2+6x+11
Answer: The amount is $14794.39 and the interest is $9794.39
Step-by-step explanation: If you deposit <em><u>$5000</u></em><u> </u>into an account paying <em><u>7.5%</u></em> annual interest compounded yearly , how much money will be in the account after <em><u>15 years</u></em>?
To find amount we use formula:
A-P(1+r/n) n*t
A = total amount
P = principal or amount of money deposited,
r = annual interest rate
n = number of times compounded per year
t = time in years
P=$5000, r=7.5, n=1 and, t=15 years
After plugging the given information we have
A= $5000 (1+0.075/1)^1.15
A= 5000 *1.075^15
A=14794.39
To find interest we use formula A=P+I'
since A= 14794.39 and P=5000
we have: A=P+I 14794.39=5000+I
I= 14794.39 -5000
I=9794.39
Answer:
can u help answer mine
Step-by-step explanation:
C
substitute a = - 1 into the expression
- (- 1) - 12(- 1)² = 1 - (12 × 1 ) = 1 - 12 = - 11 → C
