Answer:
The 95% confidence interval for the proportion of water specimens that contain detectable levels of lead is (0.472,0.766).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of 
.
In a sample of 42 water specimens taken from a construction site, 26 contained detectable levels of lead.
This means that 
95% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
The lower limit of this interval is:
The upper limit of this interval is:
The 95% confidence interval for the proportion of water specimens that contain detectable levels of lead is (0.472,0.766).
Answer:
<h3>The given set of polynomials f(x) and g(x) are closed under subtraction.</h3>
Step-by-step explanation:
Given that the functions f ad g are defined by
and 
respectively.
<h3>To show that the set of polynomials is closed under subtraction :</h3>
Now subtract the given polynomials
∴ 
- When subtracting the polynomials the variables and their exponents remains same only variation in their coefficients.
<h3>Hence the given polynomials f(x) and g(x) are closed under subtraction.</h3>
∴ are closed under subtraction,
Hence showed.
Answer:
1:2
Step-by-step explanation:
18 inches to 1 yard
We need to convert 1 yard to 36 inches
18 inches : 36 inches
Divide each side by 18
18/18 : 36/18
1:2
Answer:
b = ±16
Step-by-step explanation:
Normally to find the number we add to make it a perfect square
We take the coefficient of x
b
Divide by 2
b/2
Then square it
(b/2) ^2
In this case, we are adding 64
(b/2) ^2 = 64
Take the square root of each side
sqrt((b/2) ^2) = sqrt(64)
b/2 = ±8
Multiply each side by 2
b/2*2 = ±8 *2
b = ±16
