To determine the average water use, 109 people must be sampled.
1.9 gallons is the standard deviation.
E = 0.15 gallons maximum error
1.9 gallons on average
90% is the critical value.
1.645 is the 90% confidence interval.
sample size requirement,
n = (((z ÷ 2) × σ) ÷ E)²
n = (((1.645 ÷ 2) × 1.9) ÷ 0.15)²
n = ((0.8225 × 1.9) ÷ 0.15)²
n = (1.5627 ÷ 0.15)²
n = (10.418)²
n = 108.53 ≈ 109
As a result, the minimal sample size necessary to determine the mean water use = 109.
It is determined by dividing the average standard error by the squared of the sample size, and it decreases with increasing sample size. In other words, when the sample size is sufficiently big, the population mean approaches the population mean.
To learn more about the sample interval at
brainly.com/question/13664567?referrer=searchResults
#SPJ4
Total applications = 75
Apartments on north side of town = 4
Apartments on South side of town = 5
First person has a 4/75 chance of getting a house in the north side
P(A) = 4/75
And second person has a 3/74 chance of getting a house in the north side
P(B) = 3/74
Probability that 2 qualified applicants will be selected for the north side of town = P(A∩B) = P(A) x P(B) = (4 ÷ 75) x (3 ÷ 74) = 0.05333 x 0.04054 = 0.00216
First person has a 5/75 chance of getting a house in the south side
P(A) = 5/75
And second person has a 4/74 chance of getting a house in the south side
P(B) = 4/74
Probability that 2 qualified applicants will be selected for the south side of town = P(A∩B) = P(A) x P(B) = (5 ÷ 75) x (4 ÷ 74) = 0.06666 x 0.05405 = 0.00360
35% would be the same as .35
So multiply 270 by .35 and you woild get $94.50
Then you take 270 and subtract it by 94.50 and you get 175.50.
So your answer would be $175.50.
Hope this helps!
Never .. isoscels is unequal. I'm pretty sure
Height of the water increasing is at rate of 
<h3>How to solve?</h3>
With related rates, we need a function to relate the 2 variables, in this case it is clearly volume and height. The formula is:

There is radius in the formula, but in this problem, radius is constant so it is not a variable. We can substitute the value in:

Since the rate in this problem is time related, we need to implicitly differentiate wrt (with respect to) time:

In the problem, we are given
So we need to substitute this in:

Hence, Height of the water increasing is at rate of 
<h3>Formula used: </h3>

To Learn more visit:
brainly.com/question/4313883
#SPJ4