Hank and Debra each own two milking cows

A chemist examines 12 sedimentary samples for bromide concentraction. The mean bromide concentration for the sample date is 0.43

Umnica [9.8K]

Answer:

a) $z = 1.645$

b) Lower endpoint: 0.422cc/m³

Upper endpoint: 0.452 cc/m³

Step-by-step explanation:

Population is approximately normal, so we can find the normal confidence interval.

We have that to find our $\alpha$ level, that is the subtraction of 1 by the confidence interval divided by 2. So:

$\alpha = \frac{1-0.9}{2} = 0.05$

Now, we have to find z in the Ztable as such z has a pvalue of $1-\alpha$ .

So it is z with a pvalue of $1-0.05 = 0.95$ , so $z = 1.645$ . This is the critical value, the answer for a).

Now, find M as such

$M = z*\frac{\sigma}{\sqrt{n}}$

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

$M = 1.645*\frac{0.0325}{\sqrt{12}} = 0.015$

The lower end of the interval is the sample mean subtracted by M. So it is 0.437 - 0.015 = 0.422cc/m³.

The upper end of the interval is the sample mean added to M. So it is 0.437 + 0.015 = 0.452 cc/m³.

b)

Lower endpoint: 0.422cc/m³

Upper endpoint: 0.452 cc/m³

4 0

3 years ago

Evaluate the following<br><br><img src="https://tex.z-dn.net/?f=%20-%20%20%5Csqrt%5B4%5D%7B256%7D%20" id="TexFormula1" title=" -

poizon [28]

Ur answer is here
Hope it is helpful to u

6 0

3 years ago

The first term of a geometric sequence is equal to a and the common ratio of the sequence is r.

ololo11 [35]

Answer: (a) {a, ar, ar², ar³, ar⁴, ar⁵...}, (b) arⁿ⁻¹

For part (a), the question gives us the first term a, and then asks us to apply the common ratio r six times.

In order for ar = a, the nth term of r will have to equal 0 (this implies that n is an exponent; thus giving us the first term a, as r = 1).

Since we use this method on the first term, we must use it for the next five, in which r gains an additional exponent for every consecutive value (nth term) thereafter.

Ultimately getting: {a, ar, ar², ar³, ar⁴, ar⁵...}

For part (b), we first have to understand that the sequence does not start at 0, but at 1 for n. In order for ar = a, with n = 1, there needs to be subtraction of -1 within the exponent. So that arⁿ⁻¹

If we check and apply this, we can see that:

{ar¹⁻¹, ar²⁻¹, ar³⁻¹, ar⁴⁻¹, ar⁵⁻¹, ar⁶⁻¹...} = {a, ar, ar², ar³, ar⁴, ar⁵...} = arⁿ⁻¹ = Tn

4 0

3 years ago

A formula for a function y=f(x) is f(x)=x^2-10x,xless than or equal 5. Find f^-1(x) and indentify the domain and range of f^-1(x

evablogger [386]

F(x) =x² - 10x, f⁻¹(x) =?

1st find the missing square of x²-10x, ==> (x-5)² - 25

y= (x-5)² - 25; replace x by y and v0ce versa: x= (y-5)² -25
or
(y-5)² = x+25
y-5 = √(x+25) and y = √(x+25) -5

Domain = {x∈R: X>= 25} AND Range ={y∈R: y>= 5}

6 0

2 years ago

The librarian purchased 22 copies of a best-selling book for $385.66.

kow [346]

Answer:

$17.53

Step-by-step explanation:

$385.66 divided by 22 equals the how much each book cost

5 0

3 years ago