Answer:
The answer is 7
Step-by-step explanation:
2+8+9+9÷4=7
An ecologist is examining whether the number of fish caught in a large river basin has changed since a fire burned some of the surrounding forested area and vegetation along the river. Data in the form of fishing reports was available for a five-year period before the fire. From a random sample of 195 fishing reports before the fire, the mean catch was 6.3 fish with a standard deviation of 1.6. In a random sample of 143 reports three years after the fire, the mean catch was 7.1 fish with a standard deviation of 2.1.
Required:
What represents the standard error of the difference in the mean number of fish caught before and after the fire?
Answer:
The standard error of the difference in the mean number of fish caught before and after the fire is 0.2153.
Step-by-step explanation:
Subtraction of normal variables:
When we subtract two normal variables, the standard deviation is the square root of the sum of variances of each variable.
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.
Sample of 195 fishing reports before the fire, the mean catch was 6.3 fish with a standard deviation of 1.6.
The standard error for this sample is:
[tex]s_b = \frac{1.6}{\sqrt{195}} = 0.1246[/tex]
Sample of 143 reports three years after the fire, the mean catch was 7.1 fish with a standard deviation of 2.1.
The standard deviation for this sample is:
[tex]s_a = \frac{2.1}{\sqrt{143}} = 0.1756[/tex]
What represents the standard error of the difference in the mean number of fish caught before and after the fire?
[tex]s = \sqrt{s_a^2 + s_b^2} = \sqrt{0.1756^2 + 0.1246^2} = 0.2153[/tex]
The standard error of the difference in the mean number of fish caught before and after the fire is 0.2153.
Answer:
sqrt [ (1.6^2)/195 + (2.1^2)/143 ]
Hey guys can you guys help me thanks :)
Answer:
d
Step-by-step explanation:
60x9 =540
What is the mean of these numbers?4,5,5,2,3,3,2,8
Answer:
4
Step-by-step explanation:
Mean is the average of the set of the data in which two or more numbers are present. The mean is used to summarized the data set as the calculation of the mean includes all the values given in the data set. The mean value of the given data set is 4.
Given informationThe given numbers of the data set are,
4,5,5,2,3,3,2,8
Total numbers are 8.
MeanMean is the average of the set of the data in which two or more numbers are present. The mean is used to summarized the data set as the calculation of the mean includes all the values given in the data set.
Mean is the ratio of the sum of all the terms of the set to the the number of terms in the set.
The mean can be calculated with the following formula,
[tex]\overline x=\dfrac{\sum x}{N} [/tex]
Here N is the total number of the values in the set.
Put the values in the above formula,
[tex]\overline x=\dfrac{4+5+5+2+3+3+2+8}{8} \\ \overline x=\dfrac{32}{8}\\ \overline x=4[/tex]
Hence the mean value of the given data set is 4.
Learn more about the mean here;
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Which graph shows a proportional relationship?
A. B. C D.
Answer:
B
Step-by-step explanation:
a proportional relationship must have a straight line when graphed and it must go through the origin (0,0)
Right off the bat we can eliminate answer choice C because the line is not straight
the answer is not a nor d
the line may be straight but it does not go through the origin therefore it is not a proportional relationship
B makes a straight line and the line goes through the origin therefore B is the answer
I need help please.
Answer:
may it help you..MARK ME AS BRAINLISTS PLS
I need help please.
Answer:
Answer is C hope this helps
Step-by-step explanation:
Please show your work
Answer:
9(3+c+4)=
27+9c+36=
63+9c=
Step-by-step explanation:
9(3+c+4)=
27+9c+36=
63+9c=
What is x and y please help
Answer:
The letter "x" is often used in algebra to mean a value that is not yet known. It is called a "variable" or sometimes an "unknown". In x + 2 = 7, x is a variable, but we can work out its value if we try! A variable doesn't have to be "x", it could be "y", "w" or any letter, name or symbol.
Step-by-step explanation:
AccelGR7_Math_T6_FSQ_OL_FY21
Look at this system of linear equations.
S2x + 3y =-4
ly = 2x +4
What is the solution to the system of linear equations?
X = -2, y = 0
x= – 1, y = 2
x = 4, y = - 4
x = 2, y = 8
Answer:
x=-2 and y =0
Step-by-step explanation:
2x + 3y=-4
y=2x + 4
2x -y = -4
4y= 0
y = 0
2x -0=-4
2x =-4
x=-2
an ice cream company made 38 batches of ice cream in 7.6 hours. assuming A CONSTANT RATE OF PRODUCTION, AT WHAT RATE IN HOURS PER BATCHWAS THE ICE CREAM MADE. (hours per batch)
Answer:
5 batches per hour
Step-by-step explanation:
Is (4,3) a solution to the following system?
X-y=4
2x+y=5
(1 Point)
Yes
Οr
No
(Worth 10 points)
Answer:
No, it is not a solution
Step-by-step explanation:
Given
[tex]x - y = 4[/tex]
[tex]2x + y = 5[/tex]
Required
Is (4,3) a solution?
(4,3) implies that: [tex]x = 4\ y =3[/tex]
So:
[tex]x - y = 4[/tex]
[tex]4 - 3 = 4[/tex]
[tex]1 \ne 4[/tex]
Because 1 and 4 are not equal, then (4,3) is not a solution
f^-1(x)= -3+^3 squareroot x+4 is the inverse function of f(x)= (x-3)^3 +4 true or false
3. Classify the triangle with the given side lengths as acute, right, obtuse, 10 points
or not a triangle: 11, 13, 25
Not a triangle
Acute
Right
Obtuse
4. Classify the triangle with the given side lengths as acute, right, obtuse, 10 points
or not a triangle. 21, 28, 35
Not a triangle
Acute
Right
Obtuse
Answer:
3) Obtuse
4) Right
Step-by-step explanation:
3)
11 + 13 > 25 It is a triangle
11² + 13² = 25²
121 + 169 = 625
290 ≠ 625
Since hypotenuse is larger, the triangle is obtuse
4)
21 + 28 > 35 It is a triangle
21² + 28² = 35²
441 + 784 = 1225
1225 = 1225
Since the hypotenuse is equal to the legs, it's a Right triangle
(THIS IS NOT A TEST OR AN ASSESSMENT QUESTION)
Hugo averages 32 home runs per season with a standard deviation of 2.5. Jacob averages 27 home runs per season with a standard deviation of 1.6. Last season Hugo hit 36 home runs and Jacob hit 31 home runs. Who had more home runs relative to their usual seasonal average? Explain.
Answer:
Jacob had more home runs relative to his usual season average than Hugo did.
Step-by-step explanation:
The key solving this is to express their respective home runs in z-value forms.
Z = (x - ų)/óx
X = Current home runs
Ų = Mean
= Meanóx = Standard deviation
For Hugo,
X = Current home run = 31
Ų = Mean = 27
Óx = Stardard deviation = 1.6
Z = (x - ų)/óx
Z = (31 - 27)/1.6 = 2.5
Hope this helped!!!
The person who had more home runs relative to their usual seasonal average was Jacob.
Calculations and Parameters:Representing their home runs in z-value forms.
Where
Z = (x - ų)/óxX = Current home runsŲ = Mean= Meanóx = Standard deviation
To find the home run for Hugo,
X = Current home run = 31Ų = Mean = 27Óx = Stardard deviation = 1.6Therefore,
Z = (x - ų)/óx
Z = (31 - 27)/1.6
= 2.5
Hence, Jacob had the most home runs relative to their usual seasonal average.
Read more about standard deviation here:
https://brainly.com/question/12402189
use the expression (8x + 2) + (-9x + 7)
a. find the sum
b. explain how you know when to combine terms with variables
Need help on this math ASAP I will give the brainiest to the person who answers this correctly! Do the ones that are circled in red please. (67 points to the person who answers this)
The solution is, 0.39 = 39% of probability.
What is probability?Probability can be defined as the ratio of the number of favorable outcomes to the total number of outcomes of an event.
here, we have,
When you need to calculate probabilities involving "or" questions, in general you should use the following formula: , where P(A) is the probability of event A and P(B) is the probability of event B.
In the problem given, P(A) = yes and P(B) = male, then:
P(yes) = 33/100
= 0.33
P(male) = 20/100
= 0.20 (all male that answered the question)
P(yes and male)
= 14/100
= 0.14 (all male that answered yes to the question)
P(yes or male) = P(yes) + P(male) - P(yes and male)
= 0.33+0.20-0.14
= 0.39
=39%
Hence, The solution is, 0.39 = 39% of probability.
To learn more on probability click:
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Complete question:
One hundred people were asked, "Do you favor the death penalty?" Of the 33 that answered "yes" to the question, 14 were male. Of the 67 that answered "no" to the question, six were male. If one person is selected at random, what is the probability that this person answered "yes" or was a male?
The second group of 20 squirrels of a different breed is placed on a different ranch. The population of squirrels triples each year. Write an equation to model this new situation.
Answer: send group
Step-by-step explanation:
I’m stuck on this one. Can any one help me?
3, and apparently its "too short of an answer on this website"
find the slope of this graph, I'll give you brainliest
if you dont know please dont answer
(no links please)
thanks in advance
Answer:
(-8,1) I think, I've been working on things like this In my classes so I think I'm right. But if I'm not don't get mad please!!
Derek and his friend share two small pizzas Derek ate 7/6 of the pizzas which mixed number shows how much pizza Derek ate
Write an expression that is equivalent to 30(x + y + 1)
There are 4 oranges, 7 bananas, and 5 apples in a fruit basket.
Ignacio selects a piece of fruit at random and then Terrance
selects a piece of fruit at random.
probability of two bananas
p( two bananas )
Rory earned an 84% on his test. He answered 21 questions correctly. How many total questions were on the
test? Round to the nearest tenth if necessary
Answer:
25 questions,
$18.75
Step-by-step explanation:
Remember, to change percents to decimals, divide the number by 100 and remove the parentheses.
1. 84%, or 21 questions of Roy's test were correct.
Let's set the number of questions on the test as "x". We can then write this equation:
84% * x = 21
Simplify.
0.84 * x = 21
Divide both sides by 0.84
x = 25
There were 25 questions on the test.
2. Cheesecake Factory question
We need to find 15% of 125.
15% * 125 =
0.15 * 125 =
18.75
They need to leave a $18.75 tip.
I hope this helps! Feel free to ask any questions!
Broccoli cost 1.50 at a store. How much does 32 ounces of broccoli cost?
Answer:
48.00
Step-by-step explanation:
Answer:
48.0 hope it helps you out
Solve similar triangles (advanced)
Solve for x
x=?
Answer:
x = 1.2
Step-by-step explanation:
AD/AB = DE/BC (Similarity Theorem)
AD = 6 + 4 = 10
AB = 6
DE = 2
BC = x
Plug in the values
10/6 = 2/x
Cross multiply
10*x = 2*6
10x = 12
Divide both sides by 10
x = 12/10
x = 1.2
Will mark brainlest Thanks
Answer:
the answer is d
Step-by-step explanation:
PLEASE HELP ME 30 points!!!
Multiple Choice
Eighteen students in a class play baseball.
Seventeen students in the class play basketball.
Thirty students in the class play either or both sports
Select the Venn diagram that shows the number of students who play basketball and baseball.
Answer:
A
Step-by-step explanation:
its a bec count how many student are their an see if they add IP to 30
The Venn diagram which shows the number of students who play basketball and baseball is option A.
What is Venn Diagram?Venn diagram is a diagram denoting two or more sets which is drawn using circles inside a rectangle where the part where the two circle meet denotes the intersection of two sets.
Let A denotes the students playing baseball and B denotes the student playing basketball.
N(A) = 18
N(B) = 17
N(A ∪ B) = 30
We know,
N(A ∩ B) = N(A) + N(B) - N(A ∪ B)
= 18 + 17 - 30
= 35 - 30
= 5
Number of students who play both baseball and basketball = 5
Number of students who plays only baseball = 18 - 5 = 13
Number of students who plays only basketball = 17 - 5 = 12
This is shown in A.
Hence the correct option is A.
Learn more about Venn Diagrams here :
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help would be v appreciated thx :)
Answer:
Step-by-step explanation:
(1 point)
Only answer if you know!!! Meg was deep-sea diving at 15 feet below sea level. She dove another 7 feet below sea level. How far
below sea level was Meg?
O 8 ft below sea level
O 12 ft below sea level
O 22 ft below sea level
Answer:
22 feet below sea level
Step-by-step explanation:
she kept going down, basically in a negative way. adding to the already below sea level
What is equivalent to 4,000 centimeters? A. 4 meters B.40 meters C.400 meters D. 40,000 meters
Answer:
B. 40 meters
Step-by-step explanation:
there are 100 cm in a meter
we can divide 4,000 by 100 to see how many meters are equivalent to 4,000 cm.
4,000/100 = 40
Therefore, the answer is B. 40 meters
hope this helps :)
