Answer:
The null hypothesis is [tex]H_0: p_1 - p_2 = 0[/tex]
The alternate hypothesis is [tex]H_a: p_1 - p_2 \neq 0[/tex]
The pvalue of the test is 0.03 < 0.05, which means that we have enough evidence to accept the alternative hypothesis that he proportion of people who wear life vests while riding a jet ski is not the same as the proportion of people who wear life vests while riding in a boat.
Step-by-step explanation:
Before testing the null hypothesis, we need to understand the Central Limit Theorem and subtraction of normal variables.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
Subtraction between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
Out of 500 randomly selected people who rode a jet ski, 85% wore life vests.
This means that [tex]p_1 = 0.85, s_1 = \sqrt{\frac{0.85*0.15}{500}} = 0.016[/tex]
Out of 250 randomly selected boaters, 90.4% wore life vests.
This means that [tex]p_2 = 0.904, s_2 = \sqrt{\frac{{0.904*0.096}{250}} = 0.019[/tex]
Test the claim that the proportion of people who wear life vests while riding a jet ski is not the same as the proportion of people who wear life vests while riding in a boat.
At the null hypothesis, we test that the proportions are the same, that is, the subtraction between them is zero. So
[tex]H_0: p_1 - p_2 = 0[/tex]
At the alternate hypothesis, we test that the proportions are different, that is, the subtraction between them is different of zero. So
[tex]H_a: p_1 - p_2 \neq 0[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{s}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis and s is the standard error.
0 is tested at the null hypothesis:
This means that [tex]\mu = 0[/tex]
From the two samples, we have that:
[tex]X = p_1 - p_2 = 0.85 - 0.904 = -0.054[/tex]
[tex]s = \sqrt{s_1^2+s_2^2} = \sqrt{0.016^2 + 0.019^2} = 0.0248[/tex]
Test statistic:
[tex]z = \frac{X - \mu}{s}[/tex]
[tex]z = \frac{-0.054 - 0}{0.0248}[/tex]
[tex]z = -2.17[/tex]
Pvalue of the test and decision:
The pvalue of the test is the probability that the difference differs from 0 by at least 0.054, which is P(|Z| > 2.17), which is 2 multiplied by the pvalue of z = -2.17
Looking at the z-table, z = -2.17 has a pvalue of 0.015
2*0.015 = 0.03
The pvalue of the test is 0.03 < 0.05, which means that we have enough evidence to accept the alternative hypothesis that he proportion of people who wear life vests while riding a jet ski is not the same as the proportion of people who wear life vests while riding in a boat.
Which is the graph of f(x) = 3x?
PLEASE HELP! I AM CRYING AND NEED HELP :'(
Answer:
9300
Step-by-step explanation:
To find the total surface are of 150 boxes, all we have to do is multiply the surface area of one box ( 62 which was calculated on this question https://brainly.com/question/23446865 ) by the total amount of boxes (150)
So your answer = 150 * 62 which equals 9300
HELP PLEASEEE
A bucket contains stones and seashells. There are 18 seashells in the bucket and the ratio of stones to seashells is 2 to 1. Find the number of stones in the bucket.
Using proportions, it is found that the number of stones in the bucket is of 36.
What is a proportion?A proportion is a fraction of a total amount, and the measures are related using a rule of three.
In this problem, there are 18 seashells, and the ratio means that for each seashell, there are 2 stones, hence:
S = 18 x 2 = 36.
The number of stones in the bucket is of 36.
More can be learned about proportions at https://brainly.com/question/24372153
Alicia, Carlos, Henry, and Zoe each completed a hike. The table shows their distances and times. Match each hiker to their unit rate.
3.20 mph
3.57mph
2.77 mph
3.08 mph
Answer:
3.57 mph I think it's 3.57 but if it's not I'm sorry
Math grade 9 ,I need the answer fassstt
Answer:
Step-by-step explanation:
i dont know sorry
Answer:
a) section c
b) at a constant rate
c) below
A. 3m/s^2
B. 0 m/s^2
C. -3m/s^2
D. 1 m/s^2
Step-by-step explanation:
a) This graph models the change in velocity of time. Since when the velocity decreases over time, the acceleration is negative. This relationship is modeled in the interval from the 9th to 11th seconds which is section c.
b) If the graph is flat, it means the car is traveling at the same amount of meters per second. This means the car is traveling at a constant rate during section b.
c) During section A, the velocity in second 0 to second 4 increases by 12m/s. So, the acceleration is 3m/s^2. This is identical to finding the slope.
During section B, the velocity does not change at all, so the acceleration(and slope) is 0 m/s^2
During section C, over 2 seconds, from 9 to 11, the velocity goes from 12 m/s to 6 m/s, which is a change of -6 m/s. Therefore, the acceleration is -3m/s^2
During section D, over a span of 4 seconds(11 - 15), the velocity changes from 6 m/s to 10 m/s. That means a change of 4 m/s and the acceleration would be 1 m/s^2.
What is the difference between acute and isosceles triangle?
Answer:
The difference between acute angle and an isosceles triangle is that An acute triangle has all angles measuring less than 90º. While on the other hand The base angles in an isosceles triangle are of the same measurements.
in other words
(Isosceles triangles have two congruent sides and acute angles measure less than 90 degrees)
Step-by-step explanation:
Anthony cut a piece of metal that weighed 2,700 grams. Dionne cut a piece of metal that weighed 3,200 grams. How much heavier was Dionne’s piece, in kilograms?
A 0.5 C 50
B 5 D 500
Answer:
D: 500
Step-by-step explanation:
This is the answer because 3,200 - 2,700 = 500. Can I have a brainliest?
XxRoadToAcexX
Sam has a piece of rope that is 3 1/2 feet long he cuts the website that one piece is one 1 1/3
feet long how long is the other piece
Answer:
2 1/6 ft
Step-by-step explanation:
This problem bothers on subtraction of fraction
Given data
Total length of rope 3 1/2 feet
Let's convert mixed fraction to proper fraction = 7/2ft
First piece of rope = 1 1/3ft
= 4/3ft
Hence the second piece of the rope is = 7/2-4/3= 21-8/6= 13/6
Second piece = 2 1/6 ft
I think
dont give me files. answer on here only.
Answer:
Look at the image.
Step-by-step explanation:
a kid sits on top of a 12 foot slide, looking down with an angle of depression of 25 degrees. find the height of the slide
Answer:
Height of slide = 5 feet (Approx.)
Step-by-step explanation:
Given:
Length of slide = 12 feet
Angle of depression = 25°
Find:
Height of slide
Computation:
Length of slide = Hypotenuse
Height of slide = Perpendicular
Using trigonometry function;
Sin θ = Perpendicular / Hypotenuse
Sin 25 = Height of slide / 12
0.422 = Height of slide / 12
Height of slide = 12 x 0.422
Height of slide = 5.064
Height of slide = 5 feet (Approx.)
Find the circumference of a circle whose diameter is 12 inches. Use 3.14 for Pi
Answer:
We need to first find the radius:
half of 12(diameter) = 6 your new radius.
Formula of a circumference:
2πr
In this case
pi is 3.14 and your radius is 6 and 2 is just 2.
2 x 3.14 x 6 = 37.68 inches.
The water level at a local pier rises and falls with the tide. Yesterday, the maximum depth of the water at the pier was 8 feet, and the minimum depth was 4 feet. High tide occurred at 12:00 am and low tide occurred at 12:20 pm. Which function models the depth, in feet, of the water at the pier yesterday, as a function of the time t in minutes past high tide?
Answer: C, Bottom Left
Step-by-step explanation:
The function that models the depth, in feet, of the water at the pier yesterday, as a function of the time t in minutes past high tide is: 2 cos(π/740t)+6.
What is function model?Amplitude
A = 8 - 6
A = 2 ft
Average depth
A = (4 + 8)/2
A = 6 ft
Hence:
A+B=8
-A+B=4
1/2t=12×60×20=740
w=2π/t=π740
When t=0
d=2sin4+6=8
4=π/2
Hence:
d(t)=2 sin(π/740t + 4)+6
2 cos(π/740t)+6
Therefore the function that models the depth, in feet, of the water at the pier yesterday, as a function of the time t in minutes past high tide is: 2 cos(π/740t)+6.
Learn more about function model here:https://brainly.com/question/17281973
#SPJ2
WILL MARK BRAINLIEST
find lim h-> 0 f(1+h)-f(1)/h if f(x)= x^4
A. 13
B. 4
C. 7
D. -4
Answer: B. 4
Step-by-step explanation:
A fair die is rolled twice. What is the probability that each roll shows an odd number? (show work)
Answer:
1/4
Step-by-step explanation:
To find probability, multiply the probability of one roll times the probability of the second roll.
A die usually have 6 numbers so ill assume it has that.
1/2 or 3/6 of the sides are odd. So multiply 1/2*1/2 to get 1/4.
What is the missing length?
8 mi
Area of shaded region = 33.2 mi?
W =
miles
Components of a certain type are shipped to a supplier in batches of ten. Suppose that 50% of all such batches contain no defective components, 35% contain one defective component, and 15% contain two defective components. Two components from a batch are randomly selected and tested. What are the probabilities associated with 0, 1, and 2 defective components being in the batch under each of the following conditions?
a. Neither tested component is defective.
b. One of the two tested components is defective
Answer:
a) P (0 defective component) = 0.5
P( 1 defective component ) = 0.35
P( 2 defective component ) = 0.15
b) P( 0 ) = 0
p ( 1 ) = 1
p ( 2 ) = 0.33
Step-by-step explanation:
p( no defective ) = 0.5
p( 1 is defective ) = 0.35
p( 2 is defective ) = 0.15
Given that 2 components are selected at random
a) Given that neither component is defective
Probability of 0 defective component = 0.5
P( 1 defective component ) = 0.35
P( 2 defective component ) = 0.15
b) Given that one of the two tested component is defective
P( 0 defective ) = 0
P( 1 defective ) = P ( [tex]\frac{x=1}{x\geq 1}[/tex] ) = p( x = 1 ) / 1 - P ( x = 0 )
= ( 0.5 )^1 ( 0.5 )^0 / 1 - ( 0.5)^0 (0.5)^1
= 0.5 * 1 / 1 - 0.5 = 0.5 / 0.5 = 1
p ( 2 defective ) = p( x = 3 ) / 1 - P ( x = 0 )
= ( 0.5 )^2 ( 0.5 )^0 / 1 - ( 0.5)^0 (0.5)^2
= 0.25 / 0.75 = 0.33
Solve x3 + x2 - x - 1 =. 0 by factoring by grouping
Answer:
(x^2-1)(x+1)=0
(x+1)(x-1)(x+1)=0
x=1; x=-1
Step-by-step explanation:
Answer:
(x^2-1)(x+1)=0
(x+1)(x-1)(x+1)=0
x=1; x=-1
Step-by-step explanation:
what is the area of parallelogram BCDE
Step-by-step explanation:
[tex] \: \:\huge\mathfrak\purple{Answer...} \\ \\ here \: is \: your \: solution \\ \\ area \: of \: parallelogram = base \times height \: \\ \\ base = 10cm \: \\ \\ height = 6cm \: \\ \\ aera \: of \: pralelogram = 10 \times 6 \: \\ \\ area \: = 60 \: cm.sq \\ \\ \huge\mathfrak\red{hope \: it \: helps...}[/tex]
hi please help! ill give u a good 5 starz :)
Answer:
Option C and D!
Step-by-step explanation:
Option C because:-When 9 is placed in the box after 7, we get:-
7 ÷ 9 = [tex]\frac{7}{9}[/tex] which is correct!
7 ÷ 9 can also be written as [tex]\frac{7}{9}[/tex]. So, this Option is right since the equation is correct when 9 is placed in the box!
Option D is also correct because,When we place 9 in the box before [tex]\frac{1}{9}[/tex], we get:-
9 ÷ [tex]\frac{1}{9}[/tex] = 81
9 ÷ [tex]\frac{1}{9}[/tex] equals 9 x 9 (take the reciprocal of [tex]\frac{1}{9}[/tex])
9 x 9 equals 81 which means the equation is correct when 9 is placed in the box!
Bags of a certain brand of tortilla chips claim to have a net weight of 14 ounces. A representative of a consumer advocate group wishes to see if there is any evidence that the mean net weight is less than advertised and plans to construct a 95% confidence interval for the mean, using an SRS of 16 bags. Suppose he is not sure if the distribution of net weights is Normal. In which of the following circumstances would he not be safe to use a t procedure?
A. A boxplot of the data has multiple large outliers.
B. The mean and median of the data are nearly equal.
C. The sample standard deviation is large.
D. A boxplot of the data shows a very slight skew.
Answer:
A. A boxplot of the data has multiple large outliers.
D. A boxplot of the data shows a very slight skew.
Step-by-step explanation:
A) The normal distribution does not have outliers. The outliers are any point outside the 3σ interval which 99.7% of the data. The 0.3% data would not be outliers.
B) YEs the mean and median of the normal distribution are nearly equal. AS it is asymmetrical.
C) When the sample standard deviation is large the data is spread about the mean. The normal distribution is flatter and wider
D) The normal distribution is never skewed.If one end is longer then the distribution is not assymmetric and the normal distribution asymmetric meaning half is the mirror reflection of the other half.
So A and D indicate circumstances where he not be safe to use a t procedure.
Write an equation and solve:
Kiran is trying to save $144 to buy a new guitar. she has $34 and is going to save $10 a week from money she earns mowing lawns. she wants to know how money weeks it will take her to have enough money to purchase the guitar.
Answer:
Step-by-step explanation:
10x + 34 = 144
10x = 110
x = 11 weeks
What’s the correct answer I will mark as brainlest ASAP
Answer:
9
Step-by-step explanation:
240x.70=168 left after 30% to teacher
168/2=84 left after putting half in jar
25 students x 3=75 given to students
84-75=9 left
Silas just bought a used car for $5000. It loses value at a rate of 30% per year. The value of the car in n years is modeled by the formula f(n)=5000*(0.70)^ n-1 . Approximately how much will the car be worth in 5 years?
Answer:
$1200.50
plug 5 for n
5000(.7)^4
5000*.2401
=1200.5
Kelly goes to Six Flags with her friends. She pays $10.50 for an admission ticket and $1.25 for each ride. The total amount Kelly pays for admission and the
number of rides she rode is $29.25. Write an equation that could be used to determine
the number of rides, x, that Kelly rode?'
10.5 + 1.25x = 29.25
Calvin wrote inequalities to compare the heights, in feet, of rivers above or below flood stage.
Select all of the inequalities that are correct.
A. -10 > -9
B. 1> -18
C. -25 > -30
D. 3 < -5
E. -10 < 3
Answer:
I'm not 100% sure but I think its B. 1> -18
Move words to the blanks to make the sentence true. HELPP ME FASTTT PLEASEEE
filling, three-dimensional, unit squares
I hope this helps ^^
Answer:
Covering
two dimensional
unit squares
Step-by-step explanation:
Hope this helps! Sorry if incorrect
Find the missing side length please help!
Answer:
x = 25.4
Step-by-step explanation:
Recall: SOHCAHTOA
Reference angle = 48°
Hypotenuse = x
Adjacent = 17
Apply the trigonometric function, CAH, since the Adj and Hyp are involved
Thus:
Cos 48° = Adj/Hyp
Cos 48° = 17/x
x*Cos 48° = 17
x = 17/Cos 48°
x = 25.4061013 ≈ 25.4 (nearest tenth)
What is the value of x helppp
Answer:
The angles are vertical and x = 128*.
Step-by-step explanation:
x is the same angle as 128, because the angles are vertical.
Have a nice day! :-)
Mary has 37 sheep in her flock. If she makes one group of 7 sheep, how many equal groups of 3 sheep can be made with the remaining sheep?
Answer: 10 groups
Step-by-step explanation:
Since we know she is making a group of 7 sheep, we can do 37-7 to get 30 sheep left
If she wants to find how many groups she can make we have to do 30/3 which gets us to 10 which is the number of groups she can do
I hope this helps
What is the coefficient in the expression: 2x + 9
Answer:
2
Step-by-step explanation:
The coefficient is the number attached to the variable
The variable is the letter
The constant is ta number all on it's own
Answer:
2
Step-by-step explanation:
The coefficient is the number with the variable. The 9 is a constant.