A philanthropic organization helped a town in Africa dig several wells to gain access to clean water. Before the wells were in place, an average of 120 infants contracted typhoid each month. After the wells were installed, the philanthropic organization surveyed for nine months and found an average of 90 infants contracted typhoid per month. Assume that the population standard deviation is 40 and the number of infants that contract typhoid is normally distributed. Specify the null and alternative hypotheses to determine whether the average number of infants that contract typhoid has decreased because the wells were put in place.

Answers

Answer 1

Answer:

H0 : μ = 120

H1 : μ < 120

We Can conclude that the number of infants that contract typhoid has reduced because the wells were put in place.

Step-by-step explanation:

Average Number of infants who contracted typhoid monthly = 120

Average Number of infants who contracted typhoid monthly after well installation = 90

The null and alternative hypothesis :

H0 : μ = 120

H1 : μ < 120

Obtain the test statistic :

(Xbar - μ) ÷ s/sqrt(n)

(90 - 120) ÷ 40/sqrt(9)

-30 ÷ 13.3333

= - 2.25

The Pvalue at 95% confidence, df = n-1 = 9 - 1 = 8

Tcritical at 95%, df = 8 ; one tailed = 0.02728

Decision region :

Pvalue < α ; Reject H0

0.02728 < 0.05 ; Hence, we conclude that there is significant evidence that the average number of infants that contract typhoid has decreased because the wells were put in place.


Related Questions

What is the volume of the prism?

Enter your answer in the box as a mixed number in simplest form.

Answers

4 1/2
Try Cymath it’s great for this stuff

Answer:

V = 9/2 ft^3

Step-by-step explanation:

[tex]v = 2 \times 1 \frac{1}{2} \times 1\frac{1}{2} \\ \\ v = 2 \times \frac{3}{2} \times \frac{3}{2} \\ v = \frac{9}{2} \: \: {ft}^{3} [/tex]

I hope that is useful for you :)

Type the correct answer in the box. The area of the figure is square units.

Answers

Answer:

26 units squared

Step-by-step explanation:

multiply

5x2=10

5x2=10

3x2=6

add them together and you get

26

Answer:

26

Step-by-step explanation:

Marco is turning the expression (x-4)^2 into a trinomial. He writes down what is shown below. What is his error?

Answers

(x-4)(x-4)
=x^2-4x-4x+16
=x^2-8x+16
it’s +16, not negative. he forgot that when you add two negatives together, it becomes positive.

Answer:

Step-by-step explanation:

first, let's solve the equation ourselves.

(x-4)^2= (x-4)(x-4)= x^2−8x+16

now, we can see what's different about the two.

we can say that Marco's answer had the number 16 as a negative, when it was supposed to be positive. Marco wrote the incorrect sign.

Help Pls
Its a math question, see attachments

Answers

Answer:

1) A) 25%

2) B) 16%

3) A) 93%

Step-by-step explanation:

1)

0.25 = 25%

2)

More than 3 means, 4 and 5

0.12 + 0.04 = 0.16 = 16%

3)

x ≥ 1

So that means 1+ days (everything except 0)

0.25 + 0.18 + 0.34 + 0.12 + 0.04

0.93 = 93%

The method of tree ring dating gave the following years A.D. for an archaeological excavation site. Assume that the population of x values has an approximately normal distribution. 1271 1187 1194 1250 1268 1316 1275 1317 1275 (a) Use a calculator with mean and standard deviation keys to find the sample mean year x and sample standard deviation s. (Round your answers to the nearest whole number.)

Answers

Answer:

The sample mean year is 1261 A.D.

The standard standard deviation is of 46 A.D.

Step-by-step explanation:

Sample mean:

Sum of all values divided by the number of values. So

[tex]x = \frac{1271+1187+1194+1250+1268+1316+1275+1317+1275}{9} = 1261.4[/tex]

Rounding to the nearest whole number, the sample mean year is 1261 A.D.

Sample standard deviation:

Square root of the sum of the difference squared between each value and the mean, divided by one less than the sample size. So

[tex]s = \sqrt{\frac{(1271-1261.4)^2+(1187-1261.4)^2+(1194-1261.4)^2+(1250-1261.4)^2+(1268-1261.4)^2+(1316-1261.4)^2+(1275-1261.4)^2+(1317-1261.4)^2+(1275-1261.4)^2}{8}} = 45.8[/tex]

Rounding to the nearest whole number, the standard standard deviation year is of 46 A.D.

hellooo everyone !!! I'm an Indian !!!! Nice to meet y'all​

Answers

Nice to meet you too!!

Answer:

hi I am a Egyptian Saudi nice to meet you too

Step-by-step explanation:

Solve for x
A) -12
B) 8
C) 5
D) 7

Answers

Answer:

B. 8

Step-by-step explanation:

9x + 1 = 8x + 9

x = 8

what is the value of x​

Answers

Answer  The value of x can be found from eqautions or graphs

Step-by-step explanation:

Hi! So there is no equation, image, or otherwise added here which would make it difficult to answer your question. X is always changing based on the situation. But if you have an equation you should be able to simplify the equation and then take the quadratic formula to get the value of x. If you have  a graph you can find the rise/run. Sorry I cannot help more and I hope you find what you are looking for!

Please answer or give the steps to answer please please please this is my state test and i can’t fail

Answers

Answer:

1. 466.3ft

2. 12.1m

Step-by-step explanation:

1.

Imagine this as a triangle like shown in pic attached, then use tan to find 'x', the distance between the base of the tower and the fire:

tanA=opposite/adjacent

tan25=x/1000

x=100tan25

x=466.3ft

2.

Imagine this as a triangle like shown in pic attached, then use sine to find 'x', the kite's vertical height above the boy's hand:

sinA=opposite/hypotenuse

sin12=x/50

x=50sin12

x=10.4m

The kite's height off the ground is this plus the height of the boy's hand from the ground: 10.4+1.7=12.1m

PLZ HELP
Which is the sum of 3.15 × 10^7 +9.3 × 10^6 ? Write your answer in
scientific notation.
A. 4.08 × 10^7
B. 4.08 × 10^6
C. 0.408 × 10^8
D. 40.8 × 10^6

Answers

Answer: A 4.08x10^7

Step-by-step explanation:

Expanded form: 40800000

One school bus can hold 46 students. There are 29 students in each of the 5 fifth-grade classes. How many buses will they need in order to transport everyone to the zoo for a field trip?

Answers

29x 5 is 145 students
Divide by 46 answer is 4 buses

Answer:

4

Step-by-step explanation:

29x5=145

= 145 (divided) 46= 3.15...

4 buses

Helpppppppppppppppppppppppp

Answers

Answer:

[tex]x = 15[/tex]

165+x = 180 (linear pair)

Hence x = 15

Choose the equation that best describes the image

Answers

Answer:

80 degrees - 43 degrees = ?

Step-by-step explanation:

80-43 degrees I think x

The satellite Space Explorer flies 32000 miles in 8 hours. Find the rate of change.

Answers

Answer:

4000 miles an hour

Step-by-step explanation:

32000 ÷ 8 = 4000 miles an hour

PLEASE I NEED HELP
If f(x) = x/2 -3 and g(x) = 4x2+ x - 4, find (f+g)(x). A. 4x2 + 3/2x-7 B. 4x2 + 1/2x - 1 C. 6x2 - 7 D. 4x2 + 3/2x -1​

Answers

Answer:

A.

[tex]4x {}^{2} + \frac{3}{2} x - 7[/tex]

Step-by-step explanation:

Add theses functions

[tex] \frac{x}{2} - 3 + 4 {x}^{2} + x - 4 \\ 4 {x}^{2} + \frac{3}{2} x - 7[/tex]

POSSIBLE POINTS
aut bowling and took up sailing. His sail for his sailboat is a 45-45-90 Right Triangle. The base of the sail is 6 ft. long. How long is the hypotenu

Answers

It wouldn't let me post, so I screenshotted:

  help needed pls

Answers

A: alternate angles B: corresponding angles C: vertical angles

How many different 5-letter words can be made
a. if the first letter must be A or Y and no letter may be repeated?
b. if repeats are allowed (but the first letter is A or Y)?
c. How many of the 5-letter words (starting with A or Y) with no repeats end
in H?

Answers

Your answer would be C please trust me I’ve done this before, have a nice day (:

PLZ HELP I WILL MARK BRAINLIEST

Answers

Answer:

y=5x+1

Step-by-step explanation:

5(1)+1=6

5(2)+1=11

Step-by-step explanation:

We can see that in the table the difference between the numbers is 5.

So...

y=5x+1...

FSA Mathematics Practice Test Questions
Session 1
2.
What fraction is represented by point A on the number line shown?

Answers

There is no number line shown...
Brainliest would be nice

Is Michael correct? Will choose brainly

Answers

Yes michal is forrest

Answers please and explain

Answers

To get the answer you have to fill in the 14 for r because that is the radius. Then multiply 14 by it self to get 196 then multiply that by pie to get your answer of 615.75216.

So the answer is 615.75216

A 10.0kg rock is dropped and hits the ground below at a speed of 60 m/s . Calculate the gravitational potential energy of the rock before it was dropped

Answers

Answer:

Solution:

Mass of body, m= 10kg

velocity, v= 60m/s

Now,kinetic energy on earth= potential energy at a that point [energy conservation]

so, kinetic energy= 1/2*m* v^2

= 1/2* 60(60)^2

= 30* 60*60

= 108000 joules

Hi good morning just need help this is just a warmup not a test or anything like that.​

Answers

Answer:

75.2in = 191.008cm

Answer:

191.008cm

Step-by-step explanation:

75.2 inches =191.008cm

Consider the right triangle shown. Which statements are correct?

Answers

C, D, and E

hope this helps

QUESTION 2
The equation for this problem is what? The business has 23 employees that work 8 hours per day at $10.62 per hour.


Answers

Answer:

10/8+10.62

23*8*10.62

10.62*8+23

23+8*10.62

Step-by-step explanation:

Either one of these, I hope this helps:)

Cory has $24 more than twice as much as Stan. Together they have $150. How much money dose each have ?

Answers

Answer:

99 and 51

Step-by-step explanation:

The problem would be shown as:
2x+24 + x = 150

x is the amount of money Stan has.

Do the math and X=42. Then Plug everything in:

The answer is Cory has $108, Stan has $42.

Montraie is going to see a movie and is taking his 2 kids. Each movie ticket costs $13
and there are an assortment of snacks available to purchase for $3.50 each. How
much total money would Montraie have to pay for his family if he were to buy 4
snacks for everybody to share? How much would Montraie have to pay if he bought X
snacks for everybody to share?

Answers

cost of 4 snacks

Answer: 53

Total cost: 3.50× + 39

Find the value of x.
PLEASE HELP

Answers

To find the value of X bring the variable to the left side and bring all remaining variables to the right side simplify the values to find the result

Lola has 3 feet of ribbon. She needs to cut the ribbon into equal 2-inch strips
2
How many 2-inch strips can she cut from the 3 feet of ribbon?
2
A
15
B
90
C
21
D
145

Answers

Answer:

18

Step-by-step explanation:

1 ft=12in

3ft=36in

divide 36 by 2 and you get 18

Other Questions
Plz help me I am timed well mark brainliest if you are correct! PLEASE HELP!!!Explain how an electric car might still run on fossil fuels. 2. Find the probability that she gets a 5.*Janet rolls a regular eight-sided die with numbers 1 to 8.1/51/85/87/8 A rectangular napkin has an area of 88 square centimeters and a length of 8 centimeters.What is the width of the napkin? Anybody know number 11 in history? 3x + 2 y = 4What is the answer How did the arms race with the Soviet Union change under Reagan?A. Reagan increased the arms raceB. Reagan worked with the Soviets to maintain current levelsC. Regan continued lowering the arms raceD. Reagan had no impact on the arms race Please help on stuck on this problem What does it mean when theres an increase of white blood cells in the body?A) Nothing, the amount always variesB) There is no oxygen in the bodyC) Your body just finished fighting an infectionD) There is an infection in the body Which group of people benefited from the Social Security Act by receiving pensions andregular payments?O persons 65 and olderO WomenO teenagers 15-19 yrs old A circle has a radius of 5 centimeters. What is its area? Element X is a radioactive isotope such that every 28 years, its mass decreases by half. Given that the initial mass of a sample of Element X is 50 grams, how much ofthe element would remain after 11 years, to the nearest whole number? I will give brainly for it !!!!!!!!!!!!!!!!!!!!! Why is transcription both the same and different between chloroplasts and mitochondria? IF ANSWERD CORRECTLY WILL GIVE BRAINLIEST DO NOT GIVE ME PDFS IF YOU DO I WiLL REPORT YOUTonya sampled 35 customers leaving the grocery store to find out how long they spend shopping. The results were that two people spent less than 15 minutes shopping, 28 people spent between 15 minutes and an hour shopping, and five people spent over an hour shopping.Inference: Most customers spend less than an hour shopping.Defend or challenge the inference with at least two complete sentences. The equator is at a latitude of 0. Which latitude will have the warmest temperature? (HELP ILL GIVE BRAINLY PLEASE) Can you answer this question correctly?The area of the smaller hexagon is 38cm^{2}[/tex]What is the area of the larger hexagon? How many little hexagons can fit into the larger one? Read the first sentence of the selection.Day had broken cold and gray, exceedingly cold and gray, when the man turned aside from the main Yukon trail and climbed the high earth bank, where a dim and little-traveled trail led eastward through the fat spruce timberland.The authors syntax and use of repetition establishes a tone that is A. cynicalB. maliciousC. forebodingD. tranquil who wrote ramayana who are ram and lakshman