A field researcher is gathering data on the trunk diameters of mature pine and spruce trees in a certain area. The following are the results of his random sampling: Pine Trees Spruce Trees Sample Size 40 80 Mean trunk diameter (cm) 35 30 Population variance 160 160 Using a .10 significance level, can he conclude that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree
Answer:
As the pvalue of the test is 0.02097 < 0.1, using a .10 significance level, he can conclude that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree.
Step-by-step explanation:
Using a .10 significance level, can he conclude that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree
The null hypothesis is that they are equal(that is, subtraction between the means is 0), while the alternate hypothesis is that they are greater(that is, subtraction between the means is larger than 0). So
[tex]H_0: \mu_1 - \mu_2 = 0[/tex]
[tex]H_a: \mu_1 - \mu_2 > 0[/tex]
In which [tex]\mu_1[/tex] is the mean pine trees height while [tex]\mu_2[/tex] is the mean spruce trees height.
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]
Mean trunk diameter (cm) 35 30:
Pine trees - 35
Spruce trees - 30
The sample mean is given by the subtraction of the means. So
[tex]X = 35 - 30 = 5[/tex]
Sample Size 40 80
Population variance 160 160
This means that the standard error for each sample is given by:
[tex]s_1 = \frac{\sqrt{160}}{\sqrt{40}} = 2[/tex]
[tex]s_1 = \frac{\sqrt{160}}{\sqrt{80}} = \sqrt{2}[/tex]
The standard error of the difference is the square root of the sum squared of the standard error of each sample.
[tex]s = \sqrt{2^2 + (\sqrt{2})^2} = \sqrt{6} = 2.4495[/tex]
Test statistic:
[tex]z = \frac{X - \mu}{s}[/tex]
[tex]z = \frac{5 - 0}{2.4495}[/tex]
[tex]z = 2.04[/tex]
Pvalue of the test:
Probability of a sample mean larger than 5, which is 1 subtracted by the pvalue of Z when X = 5.
Looking at the z-table, z = 2.04 has a pvalue of 0.9793.
1 - 0.9793 = 0.0207
As the pvalue of the test is 0.02097 < 0.1, using a .10 significance level, he can conclude that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree.
A study will be conducted to investigate whether there is a difference in the mean weights between two populations of raccoons. Random samples of raccoons will be selected from each population, and the mean sample weight will be calculated for each sample.
Which of the following is the appropriate test for the study?
A. one-sample zz-test for a population proportion
B. A one-sample tt-test for a population mean
C. A two-sample tt-test for a difference between sample means
D. A two-sample tt-test for a difference between population means
E. A two-sample zz-test for a difference between population proportions
Answer:
D. A two-sample t-test for a difference between population means
Step-by-step explanation:
Since in the question it is mentioned that there would be the random samples taken from each population of raccons and the weight of the mean sample would be determined for each kind of sample
So here the test for the study that should be considered is two sample t-test so that it would create a difference between the population means
Hence, the option d is correct
What are the coordinates of point A" if triangle
ABC is reflected over the y-axis and then
translated by the rule (22, y) + (x – 5, y – 5) ?
A. (-2,-2)
B. (2,-2)
C. (-2,2)
D. (2,2)
Answer:
Reflected OVER Y makes A
A (-7,3) -> (7,3)
Translated makes
A (7,3) -> (7-5, 3-5) = (2,-2)
B)
Step-by-step explanation:
Please help, I’ll mark you as brainiest if you’re correct !!!
Answer: i think c
Step-by-step explanation:
Answer:
I believe the answer is B i am not 110% sure tho
HELP ME PLEASE PLEASE PLEASE
Answer:
( 4 x 10 y )
Step-by-step explanation:
Determine the period of the function y = Negative 2 sine (StartFraction pi Over 2 EndFraction) x.
a.
2
c.
-2
b.
3.14
d.
4
Answer: D. 4
Step-by-step explanation:
-5 = 1 / 3 ( -1 - w )
plz help with step by step answer
Step-by-step explanation:
[tex] - 5 = \frac{1}{3} ( - 1 - w) \\ \frac{1}{3} ( - 1 - w) = - 5 \\ - 1 - w = - 5 \div \frac{1}{3} \\ - 1 - w = - 5 \times 3 \\ - 1 - w = - 15 \\ - w = - 15 + 1 \\ - w = - 14 \\ w = 14[/tex]
Help me!!!!!!!!!!!! And look at the picture plzzzz!!!!
Answer: 72
Step-by-step explanation:
Set it up as a ratio
[tex]\frac{12}{15} =\frac{x}{90} \\15x=1080\\x=72[/tex]
Doors for the small cabinets are 11.5 inches long. Doors for the large cabinets are 2.7 times as long as the doors for the small cabinets. How many large doors can be cut from a board that is 10 feet long?
Answer:So if you take the small cabinet door length which is 11.5 inches long and multiply by a factor of 2.3 you get the total length of the large cabinet doors, which is 26.45 inches
Step-by-step explanation:
please help!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
A) 40
B) 20
Step-by-step explanation:
By Length · Width · Height
A) (5) · (4) · (2) = 40
For part B, the length and width are the same, but the depth (height) of the water is only one foot, so we can replace the height value from the first equation with 1.
B) (5) · (4) · (1) = 20
Each side of the park is 9meters long what is the perimeter
Answer:1125
Step-by-step explanation:
w=width
w+20=length
P=2l+2w
140=2(w+20)+2w
140=2w+40+2w
140=4w+40
140-40=4w
100=4w
w=100/4
w=25 m
l=25+20=45 m
A=lw
A=45*25
A=1125 sq m
In AHIJ, h = 160 inches, i = 910 inches and ZJ=28°. Find the area
of AHIJ, to the nearest square inch.
Answer:
34178
Step-by-step explanation:
deltamath
1 Krista has 10 cups of gelatin. If each bowl holds 3 cup, how many bowls can she fill?
Answer: Krista can fill 3 1/3 bowls of gelatin.
PLEASE HELP QUICK PLS PLS PLSSSSS
Please help!!!!!!!!!
10+6+9+13+7= 45
and divide it by 5
the answer is 9
the answer is 2.74, this is easy to figure out if you want to you can look up a claculator for it
how do you find the percent of discount if the original price is $578 and the sale price is $78.76
Answer: 86%discount approx
Step-by-step explanation:
You need to think about how the original price (578) is 100% of the price and that the sale price (78) is just a percentage of that. To discover how much of that 100% the price 78 is, you can write the formula:
578:100=78:x
X=(78*100)/578
X=14 %
Once you know that 78 represents the 14% of the whole price (100%-578) you just have to subtract that amount from the whole to understand which percent of discount has been applied: 100-14 = 86%
Mr. Rice needs to replace the 166.25 ft of edging on the flower beds in his backyard. The edging is sold in lengths of 19 ft. each. How many lengths of edging will Mr. Rice need to purchase?
Answer:
6.11 or 6.12
Step-by-step explanation:
You will have to divide 116.25 by 19
to find the length Mr.Rice will need to purchase
which is 6.11842105
Triangle ABC is equilateral. What is the measure of angle B?
Answer:
60
Step-by-step explanation:
Equilateral triangles- all 3 angles are 60
6. The angle of depression from the top of a tower to a boulder on the ground is 38°. If the tower is 25 m high,
how far from the base of the tower is the boulder?
A television is on sale for 30% off. The sale price is $322. What is the original price of the television?
PLEASE HELP QUICK
Answer:
$460
Step-by-step explanation:
Let
x = original price of the television
Sale price = $322
Discount = 30%
x - 30% of x = 322
x - 0.3 * x = 322
x - 0.3x = 322
0.7x =322
x = 322/0.7
x = $460
x = original price of the television = $460
The height of a triangle is 5 more than double the base length. If the height of the triangle is 74mm, what is the base length of the triangle
Answer:
height = 5+2xbase
74 = 5+2xbase
subtract 5 from both sides
69 = 2xbase
divide both sides by 2
34.5mm = base length
Four students, Kaylee, Xavier, Ruby, and Brandon, line up one behind the other. How many different ways can they stand in line?
40 points && brainliest! pls help.
Four students, Kaylee, Xavier, Ruby, and Brandon, line up one behind the other. So, there are 24 different ways they can stand in line.
How does factorial work?Factorial of a positive integer is the result of the repeated multiplication of all the integers from 1 till that considered integer.
Thus, if we want to take the factorial of 'n',(n being a positive integer), then:
[tex]n! = 1 \times 2 \times \cdots \times (n-1) \times n[/tex]
Four students, Kaylee, Xavier, Ruby, and Brandon, line up one behind the other.
The different ways they can stand in line = 4!
[tex]= 4 \times 3 \times 2 \times 1\\\\= 12 \times 2\\\\24[/tex]
So, there are 24 different ways they can stand in line.
Learn more about factorials here:
https://brainly.com/question/16036678
#SPJ2
Find the Perimeter of the figure below, composed of a rectangle and a semicircle. Round to the nearest tenths place.
What do you want to know
Answer:
the point of living life if there's any also what's after death
Liza went out for pizza with her mom. Their meal cost $32. Sales tax is 5% and they decide to leave 15%
for average service. What is their total bill?
Answer:
7
Step-by-step explanation:
fdgrgeag
What is the volume of the rectangular prism?
5 cm
8 cm
1 cm
cm3
Answer: 40 PLEASE MARK BRAINLEST
Step-by-step explanation:
Can anyone help? I struggle with Algebra
What is the measure of the central angle that goes with the given arc measure shown below
I need help ASAP pls help me
Answer:
ΔABC ≅ ΔPQR
Step-by-step explanation:
therefore, AB has the same length as PQ
therefore, BC has the same length as QR
therefore, AC has the same length as PR
∡A = ∡P
∡B = ∡Q
∡C = ∡R
who is spongeborb ???
Answer:
Spongeborb???
I don't know a spongeborb, but I DO know a spongebob
Spongebob is my homie, he lives right next door to me in his pineapple...and occasionally, I make him do my dishes
Answer: spongeborb?
SpongeBob SquarePants is the title character and protagonist of the American animated television series of the same name. He is a sea sponge who works as a fry cook at the Krusty Krab, a fast food restaurant known for its signature burger, the Krabby Patty.
Step-by-step explanation:
Have a nice day!