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
Answer:
Step-by-step explanation:
the space (usually measured in degrees) between two intersecting lines or surfaces at or close to the point where they meet.
Answer:
x=1
Step-by-step explanation:
6/12 = x/2
Simplify the left side by dividing the top and bottom by 6
1/2 = x/2
Using cross products
2x =2
Divide by 2
2x/2 =2/2
x=1
Answer:
$212.40
Step-by-step explanation:
180+ (180* 18%)= Total Cost
180+ 32.40= Total Cost
212.40= Total Cost
Answer:
x = 28
Step-by-step explanation:
7(8 - x) = -5x
56 - 7x = -5x Distribute 7 to the parenthesis
56 = 2x Add -7x to both sides
28 = x Divide 2 to both sides