There is concern that increased industrialization may be increasing the mineral content of river water. Ten years ago, the silicon content of the water in a certain river was 5 mg/L. Eighty-five water samples taken recently from the river have mean silicon content 5.4 mg/L and standard deviation 1.2 mg/L. a. Find the P-value. b. Do you believe it is plausible that the silicon content of the water is no greater than it was 10 years ago

Answers

Answer 1

Answer:

a) P value = 0.0013

b) No, it is not plausible that the silicon content of the water is no greater than it was 10 years ago

Step-by-step explanation:

The null hypothesis here is “Mean is equal to 5” while alternate hypothesis is that “Mean is greater than 5”

Given  

Mean = 5, x’ = 5.4 and sigma = 1.2 and n = 85

Z = x-u’/sigma/sqrt n

Substituting the given values, we get –  

Z = 3.02

A) P value = 0.0013 which is less than 0.05 and thus we will reject the null hypothesis

B) There is enough evidence to reject the null hypothesis  


Related Questions

Please help quick (timed)

What isometric transformation was Applied to triangle XYZ ?

Translation ?
Reflection ?
Dilation ?
Rotation ?

Answers

Answer:

Rotation

Step-by-step explanation:

Ramon invested a total $9,700 into two accounts, account 1 earns 6% simple interest and account 2 earns 4% simple interest. After one year, the total interest earned from both accounts was $466. Let X be the amount you invested in account 1 and y be the amount invested in account 2

Answers

Answer:

In the account that paid 3% Ramon put $800

In the account that paid 6% Ramon put $1,600

Step-by-step explanation:

Answer:

x+y= 9700 & 0.06x + 0.04y=466

Step-by-step explanation:

let X & Y be each account.  Together, they are $9,700.

So, x+y=9700

thus, account 1 (x) earns 6 %. which converted to decimal is 0.06

account 2 (y) earns 4 % which converted is 0.04

It also said that both accounts were $466, after 1 year.

0.06x+0.04y=466

Use the picture below to answer the question.
6 ft
The angle of elevation from the swimmer to the lifeguard is 35*
Find the distance x from the swimmer to the base of the lifeguard chair.
Find the distance y from the swimmer to the lifeguard.
Round to the nearest tenth as needed.
Select the correct response
x=7.3ft, y= 3.4ft
x=8.6 ft y=10.5 ft
x=3.4ft, y=73 ft
x=10.5 ft, y= 8.6 ft

Answers

Answer: x = 8.6 y=10.5

Step-by-step explanation:

This is a question about trig identities, familiarize yourself with sin, cos, tanIn this problem, our value for degrees is 35 and our opposite side is 6ftOur variables to solve are x and y, x being the adjacent size and y being the hypothenusey has to be the longest size, it being the hypothenuse, so eliminate the first and last optionstan = opposite/adjacent so,  tan(35)=6/x.solve this equation for x, yielding 8.6For y, using the fact that sin=opposite/hypothenusesubstitute and get the equation sin(35)=6/ysolve and get y =10.5x=8.6 and y= 10.5

What is the greatest common factor for 27 and 51

Answers

Answer:

27:-3×9

51:-3×17

In 27 and 51 the common one is 3 and hence it is the greatest common factor.✓✓

if you want smallest or lowest common factor then you have to take the common 3 as one and multiply like this:-3×9×17=459 is the Lowest common factor.

*mark me brainliest

If I ate 300 apples and there were 29 left how many were there in the start. Or before I ate the apples.

Answers

329 apples!

300+29=329

 !!!MAJOR HELP AND NO LINKS AND IF YOU DONT KNOW BUT YOU STILL ANSWER, I WILL REPORT IF YOU SAY SOMETHING THAT IS NOT AN ANSWER!!!
Twice a number, decreased by 4, Is at least 12.Which of the following is a solution?
Image above

Answers

Answer:

2x-8=1/2-2

Step-by-step explanation:

Answer: 8

So, the first approach with this problem you should take is writing out the mathematical expression in association to what is being described.

To help break down the statement, let's look over it "twice a number (i.e., the number we are looking for multiplied by 2), decreased by 4 (subtraction), is at least 12 (equals that value).

Therefore,

2(x) - 4 = 12

Using algebra to isolate the x variable, we find that:

x = 8

I hope that I understood what was being asked enough to help!

 what’s the y intercept and slope of all of them? I give Brainly

Answers

9514 1404 393

Answer:

slope: 6; y-intercept: -3slope: 11; y-intercept: -1slope: 2; y-intercept: -13slope: 1; y-intercept: -6

Step-by-step explanation:

The slope is found using the slope formula. It works well to choose ordered pairs that only differ by 1 in their x-value.

  m = (y2 -y1)/(x2 -x1)

The y-intercept is the y-value when x=0. If it is not in the table, it can be found from one point and the slope.

  b = y1 -m·x1

__

1) slope = (9 -3)/(2 -1) = 6

  y-intercept = -9 -6(-1) = -3

__

2) slope = (21 -(-1))/(2 -0) = 22/2 = 11

  y-intercept = -1 . . . from table for x=0

__

3) slope = (-9-(-11))/(2-1) = 2

  y-intercept = -11 -(2)(1) = -13

__

4) slope = (-4 -(-5))/(2 -1) = 1

  y-intercept = -7 -1(-1) = -6

Read the situations in the table below. Then drag a graph and equation to represent each situation. Indicate whether each of the relationships is proportional or non-proportional.

Answers

The equation for situation 1 is y=4x and is directly proportional and the situation two will have equation y=x+4 and is not proportional.

What are linear equations?

Linear equations help in representing the relationship between variables such as x, y, and z, and are expressed in exponents of one degree. In these linear equations, we use algebra, starting from the basics such as the addition and subtraction of algebraic expressions.

Given here, graph 1 varies 4 times the x value every time there is an increase of 1 in the x-axis and in graph 2 it is a linear equation with intercept at 4 and thus the graph increases with +4 and   A proportional relationship exists between two values x and y when they can be expressed in the general form y = kx,

Hence, The equation for situation 1 is y=4x and is directly proportional and the situation two will have equation y=x+4 and is not proportional.

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What is the length of the altitude of the equilateral triangle below? A. 6 B. 2 C. 2/3 D. /48 E. 36 F. 6 /3​

Answers

Answer:

Step-by-step explanation:

It’s A

The length of the altitude of the right triangle given is 6.

What is Right Angled Triangle?

Right angled triangle are those triangle for which one of the angle is 90 degrees.

The given triangle is an equilateral triangle.

All the sides are equal.

Each of the side = 4√3

Altitude divides one of the side in to two equal halves.

Using Pythagoras theorem,

Altitude = √(4√3)² - (2√3)²

             = √(16×3) - (4 × 3)

             = √48 - 12

             = √36

             = 6

Hence the altitude of the triangle is 6.

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Find y'' for x² + y⁴ = 20​

Answers

now, this is implicit differentiation, so it comes with the assumption that "y" is a function in "x terms", as opposed to a plain vanilla variable, whilst "x" is just that, so

[tex]\cfrac{d}{dx}[x^2+y^4=20]\implies 2x+\stackrel{chain~rule}{4y^3\cdot \cfrac{dy}{dx}}=0\hspace{5em}\cfrac{d}{dx}\left[ 2x+4y^3\cdot \cfrac{dy}{dx}=0 \right] \\\\\\ 2+\stackrel{product~rule}{\left( 12y^2\cdot \cfrac{dy}{dx}+4y^3\cdot \cfrac{d^2y}{dx^2} \right)}=0\implies 2+12y^2\cdot \cfrac{dy}{dx}+4y^3\cdot \cfrac{d^2y}{dx^2}=0 \\\\\\ 2+12y^2\cdot \cfrac{dy}{dx}=-4y^3\cdot \cfrac{d^2y}{dx^2}\implies {\Large \begin{array}{llll} \cfrac{2+12y^2\cdot \frac{dy}{dx}}{-4y^3}=\cfrac{d^2y}{dx^2} \end{array}}[/tex]

In the diagram , r = 3 and x = 45. What is the volume of the remaining part of the hemisphere to the nearest tenth of a cubic unit? HINT subtracting 45 degrees leaves about % of the Hemisphere

Answers

The best approximation is 49.7 unit^3

to solve 2/5 x = 14, you multiply both sides of the equation by 5/2. your friend divides both sides of the equation by 2/5. who is right? explain.

Answers

Answer:

both are right

Step-by-step explanation:

2/5x = 14

multiply both sides by 5/2:

(5/2)(2/5)x = 14(5/2)

x = 70/2 = 35

However, dividing by 2/5 is the same as multiplying by 5/2, so you are BOTH right.  Dividing by a fraction is the same as multiplying by the reciprocal of the fraction.

What is 1/6 divided by 4​

Answers

Answer: 1/24 or 0.0416

Step-by-step explanation:

this is so easy its 4.5

7X -6Y=-3 what is the slope of the parallel and perpendicular line

Answers

Answer:

parallel: 7/6perpendicular: -6/7

Step-by-step explanation:

You want the slopes of the lines parallel and perpendicular to 7x -6y = -3.

Slope

The slope is the x-coefficient when the equation is in slope-intercept form:

  y = mx +b

Solving for y gives ...

  -6y = -7x -3

  y = 7/6x +1/2 . . . . . divide by -6

The slope of the given line is 7/6.

Parallel

A parallel line will have the same slope: 7/6.

Perpendicular

A perpendicular line will have opposite reciprocal slope: -6/7.

Help me with this question

Answers

9514 1404 393

Answer:

  A.  (0, -1)

Step-by-step explanation:

The x-coordinate of the y-intercept is always zero (eliminates choices B and D. Here, we can see that extending the given line will make it cross the y-axis below the x-axis, where y-values are negative (eliminates choice C).

We can see that the slope of the line is a rise of 1 for a run of 2 units to the right. The point that is 1 above and 2 right of (-2, -2) is (0, -1), the y-intercept.

checking account a charges a montly service fee of 3 and a per check fee of .02 while checking account b charges a montly service fee of 2 and a per check fee of .03 how many checks would a person have to write for the two accounts to cost the same

Answers

Answer:

good morning I was just asking when will I be

29) Which is a counterexample that shows the following conjecture is false: "If 21 and 22 are complementary, then one of the angles is obtuse" ? A. m/1 = 90° and m42 = 90° B. m/1 = 53° and m42 = 127° C. mz1 = 100° and m42 = 80° D. mz1 = 45° and mz2 = 45​

Answers

D. mz1 = 45° and mz2 = 45 are complementary angles (mz1 + mz2 = 90°), but neither angle is obtuse (greater than 90°), so the guess is wrong. This is a counter-example to show.

What are supplementary angles?

A supplementary angle is an angle where the sum of two angles is 90 degrees. That is, if angle A and angle B are complementary, angle A measurement + angle B measurement = 90 degrees. Supplementary angles may be adjacent (having a common vertex and edge) or non-adjacent (having no common vertex or edge), but they always complement each other.

There are various kinds of angles to study.

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Select all of the following that are quadratic equations.
3x ^2 + 5x - 7 = 0
x ^3 - 2x ^2 + 1 = 0
2x - 1 = 0
5x ^2+ 15x = 0
6x - 1 = 4x + 7
x ^2 - 4x = 4x + 7

Answers

Answer:

3x ^2 + 5x - 7 = 0

5x ^2+ 15x = 0

x ^2 - 4x = 4x + 7

Step-by-step explanation:

Just find a equation with a degree of 2 and boosh


A 94-ft tree casts a shadow that is 110 ft long. What is the angle of elevation of the sun?

Answers

Answer:

Step-by-step explanation:

Setting up a diagram would be helpful here, so we should have the vertical leg representing the 84-ft. tree and the horizontal leg representing the 120 ft. shadow.  With the two measurements we are given, we should use the tangent ratio, opp/adj,  to set up an equation to solve for the angle of elevation. So the equation will be:

tan θ = 84/120.  Using the tan inverse function on the calculator, we have tan-1( 84/120) = θ and, rounding our decimal value to the nearest 10th, we have θ =35°.  

consider the trinomial 15x² - 34x - 16.
List all the factor pairs for -240.

Answers

Answer: To find the factor pairs for -240, we can use the following steps:

Find the prime factorization of -240: -240 = (-2) * (-2) * (-2) * (-3) * (-5)

For each prime factor, there are two possible factor pairs: (-1) and (1), and (-n) and (n). For example, for the factor -2, the possible factor pairs are (-1) and (1), and (-2) and (2).

The factor pairs for -240 are: (-1) and (1), (-2) and (2), (-3) and (3), (-5) and (5), (-6) and (6), (-10) and (10), (-15) and (15), (-30) and (30).

Thus, the factor pairs for -240 are: (-1, 1), (-2, 2), (-3, 3), (-5, 5), (-6, 6), (-10, 10), (-15, 15), and (-30, 30).

Step-by-step explanation:

The baby giraffe weighed 132 pounds at birth. He gained weight at a steady rate for the first 7 months until his weight reached 538 pounds. How much did he gain each month? Need an equation

Answers

Answer: 58lbs

Step-by-step explanation:

Calculate the difference between 132 and 538. You can do this by subtracting.

538

- 132

132 + 7r = 538r = 58 pounds


What’s the answer ?
Solve |2x - 3| ≥7

Answers

Answer:

x ≤ −2 or x ≥ 5

Step-by-step explanation:

Isolate the variable by dividing each side by factors that don't contain the variable.

please help will give brainliest

Answers

Answer:

V = 170 in³

Step-by-step explanation:

The volume of a triangular pyramid

V = (1/3)Ah

where A = area of the triangular base, and H = height of the pyramid

---------------------------

A = (1/2)(12)(5)

A = 30

V = (1/3)(30)(17)

V = 170 in³

how to figure out how many data points are in a data set

Answers

Answer:

Step-by-step explanation:

read the data numbers

Part B
Omar uses the information in the table and the following steps to estimate the
number of blue marbles in the jar.
• He considers the smallest ratio of blue marbles: 58/200.
He considers the largest ratio of blue marbles: 82/200.
• He estimates that there are most likely between 580 and 820 blue marbles in the jar

Is Omar's estimate reasonable? Explain.

Answers

Answer:140

Step-by-step explanation: It is a really big number not the most reasonable answer for the low amount of marbles their are in the jar adding 58 and 82 gives you your answer

Cones A and B both have volume 48pi cubic units, but have different dimensions. Cone A has radius 6 units and height 4 units. Find one possible radius and height for Cone B.

Answers

The possible radius and height for Cone B are 3 units and 16 units respectively

How to determine the radius and height of the cone

The formula for calculating the volume of a cone is expressed mathematically;

Volume = 1/3 πr²h

Given that;

π takes the value 3.1 4r is the radius of the coneh is the height of the cone

From the information given, we have that;

Both cone A and B have volume of 48πCone A has 6 units and height of 4 units

Now, let the height of cone B be 16 units

Substitute the value into the formula, we have;

48π = 1/ 3 × π × r² × 16

multiply the values, we have

48 = 16r²/3

cross multiply

16r² = 144

Divide both sides by 16

r² = 144/16

r² =9

Find the square root of both sides

r = 3units

Hence, the values are 3 units and 16 units

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The guidelines for a wheelchair ramp suggest that the ratio of the rise to the run be no greater than 1 : 12


A. Which wheelchair ramps follow the guidelines

A. A ramp with a length of 30 feet and a height of 3 feet

B. A ramp with a length of 20 meters and a height of 0.5 meters

C. A ramp with a length of 384 inches and a height of 32 inches

D. A ramp with a length of 1 feet and a height of 12 feet




B. A wheelchair ramp provides access to a building with a front door that is 2.5 feet above the sidewalk. Which best describes the possible length(s) for the ramp that will follow the guidelines.

Let x represent the length (in feet) of the ramp

A. X < 30

B. X > 30

C. X ≥ 30

D. X ≤ 30

Answers

Answer:

Q1. Answer: According to the guidelines, the ratio of the rise (height) to the run (length) of a wheelchair ramp should be no greater than 1:12.

Option A: A ramp with a length of 30 feet and a height of 3 feet. The ratio of the rise to the run is 3/30 = 1/10, which is less than 1:12, so this ramp follows the guidelines.

Option B: A ramp with a length of 20 meters and a height of 0.5 meters. The ratio of the rise to the run is 0.5/20 = 1/40, which is less than 1:12, so this ramp follows the guidelines.

Option C: A ramp with a length of 384 inches and a height of 32 inches. The ratio of the rise to the run is 32/384 = 8/96 = 2/24, which is less than 1:12, so this ramp follows the guidelines.

Option D: A ramp with a length of 1 feet and a height of 12 feet. The ratio of the rise to the run is 12/1 = 12, which is not less than 1:12, so this ramp does not follow the guidelines.

Therefore, the ramps that follow the guidelines are options A, B, and C.

Q2. Answer: The guidelines for a wheelchair ramp suggest that the ratio of the rise (height) to the run (length) of the ramp should be no greater than 1:12. In this case, the rise is 2.5 feet and the run is the length of the ramp (x feet). The ratio of the rise to the run is 2.5/x.

To follow the guidelines, the ratio of the rise to the run should be no greater than 1:12, or 1/12. Therefore, the length of the ramp (x) should be greater than or equal to 2.5/1/12 = 30 feet.

Therefore, the correct answer is C: X ≥ 30.

Step-by-step explanation:

Pls help me answer the question down in the image below

Answers

Using the concept of proportion to find the value of x in the similar triangle, x is equal to 6.67

What is Similar Triangle Theorem

Similar triangle theorem states that if two triangles have corresponding angles that are equal, then the sides of the triangles are proportional to each other. This theorem can be used to solve problems involving triangles, such as finding the lengths of missing sides.

We can use the concept of ratio to find the value of x.

12 / 5 = 16 / x

Cross multiply both sides and solve for x

12 × x = 16 × 5

12x = 80

x = 80 / 12

x = 6.67

The value of x is 6.67

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An initial amount of $1300 is invested in an account at an interest rate of 1% per year, compounded continuously. Find the amount in the account after five years. Round your answer to the nearest cent.

Answers

Answer:

65, given the amount of $1300 times 0.01 percent times 5 years would equal $65 over 5 years, to break it down, multiply 1300 times 0.01 times 5.

Step-by-step explanation:

John needs to print 36 copies of his colored poster. His HP printer can print 16 copies in 5 minutes. His Epson printer can print 4 copies in 1 minute.

9a) Enter an equation that can be used to find the number of minutes, t, John would take to make 36 copies if he used both printers. Enter your response in the first response box. (DO NOT PUT SPACE IN YOUR ANSWER. USE t AS YOUR VARIABLE. Write fractions using the correct order of operations.)Plz help

Answers

Answer:

It would probably be 36t

Step-by-step explanation:

because if you think about It.

It is mainly asking you how long it is going to take, so you need a a equation to find the answer.

-John needs 36 copies

- Hp printers out 16 in 5 minutes

- Epson printer out 4 in 1 minutes

so 36 x t or 36t

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Can some please help me write a loving good morning text Which statement BEST describes the importance of well-constructed carefully worded e-mails?1. E-mail is a communication tool that is used often in the health care setting2. E-mallis another way that patients can effectively communicate3. E-mails are considered legal documents and may be used in legal matters.4. E malls are often read by more than one person Division of mixed numberrss Solve the inequality: 4-3x What happens if you run a delete command that does not contain a where clause? Graph: y - 3 = 1/2 (x + 2) 1.M/s Kanwarlal & Sons are opening a new showroom of readymade garments at New Cloth Market, Surat. The inauguration is fixed for Sunday, 14 April 2021 at 10.00 a.M. Write a formal invitation on their behalf . 7. (a) A homeowner wishes to replace the three identical steps leading to her front door with a ramp. Each step is 10 cm high and 35 cm long. Find the length of the ramp. Give your answer correct to one decimal place. ABC Bank requires a 20% down payment on all its home loans. If the house is priced at $165,000, what is the amount of the down payment required by the bank Write a paragraph about the idea of land and the conflict between First Nations and Europeans after the Treaties of 1713.Post a a fake link and your account will get deleted. What is the area of the composite figure below? Refer to the figure in the picture to determinethe measure of each given angle. An airplane travels about 1,500 Km in a straight line between Toronto and Winnipeg. However, the plane must climb to 10,000 m during the first 200 Km, then it must descend 10,000 m during the final 300 Km.a) How much distance do the climb and descent add to the flight?b) The airplane averages a speed of 600 km/h. Do climbing and descending 10 000 m add hours, minutes of second to the flight? Explain.Please help I do not understand how to do this. A pet shelter has 5 cats and 9 dogs.Enter the ratios in the boxes.ratio of cats to all animals:ratio of dogs to cats: Which statement is true for log3(x+1)=2? 4x+4y=4 3x+y=10 solve by elimination The boatbill is present in a density of at least one pair per 20 acres at the same time that two different types of plants are dominant. What are these plants?A. Weeds and grassesB. Grasses and ShrubsC.Shrubs and small treesD. small trees and canopy trees Which one should i get? everything else being equal, a firm considering outsourcing can be reasonably certain that: ____ 2. Find the surface area of the solid:3.1 ft8 ft6 ftCan you show me how you got the answer pls