Answers:
a) The 40 students selected to participate in the survey (8*5 = 40).b) The population is the set of all students in his five classes combined.===========================================================
Explanation:
The teacher wants to know something about his students, so he's only focused on them and no one else. The teacher has 5 classes. Let's say each class has 40 students. That would mean 40*5 = 200 students total are taught by this bio teacher, and these 200 students make up the population. We're not considering any other student in this school since they are not in this teacher's class.
Once the population is well formed and well defined, the sample is drawn from the population. Specifically, the teacher is randomly selecting 8 people from each class. The teacher is using the stratified sample technique. Each class is a stratum, ie, a separate group. The plural of stratum is strata. Because there are 5 classes, and 8 people selected per class, this leads to an overall sample of 8*5 = 40 students. Those 40 students chosen randomly fairly represent the 200 students in the population. Therefore, this process is fairly unbiased.
Be sure not to mix stratified sampling with cluster sampling. Cluster sampling is not performed here because that would mean the teacher randomly selects say 2 classrooms (ie clusters) and samples everyone in each cluster selected. Instead, the teacher is only picking representatives from each class, as if those people were elected to office. As you can probably guess, cluster sampling can be expensive in terms of time and money, so if you need to apply a cluster sample, then it's best to make the clusters as small as possible but also make sure each cluster is reflective of the population.
find the probability that a randomly selected point within the circle falls in the red shaded area round to the nearest hundredth r = 4 cm 2.5 cm 3 cm 3 cm
Answer:
[tex]p\approx 0.39[/tex]
Step-by-step explanation:
We are given a circle of radius 4 cm, and a triangle inscribed within the circle with a vertical height of 6.5 cm and a base of 6 cm.
To find the probability a randomly selected point lands in the red area, we can divide the red area by the total area.
The area for a circle is given by:
[tex]A=\pi r^2[/tex]
Since the radius is 4 cm, the area of the circle or total area is:
[tex]A=\pi (4)^2=16\pi \text{ cm}^2[/tex]
The area for a triangle is given by:
[tex]\displaystyle A=\frac{1}{2}bh[/tex]
The base of the triangle is 6 cm total and the vertical height is 6.5 cm. Therefore, the area is:
[tex]\displaystyle A=\frac{1}{2}(6)(6.5)=19.5\text{ cm}^2[/tex]
The probability of landing in the red shaded area is:
[tex]\displaystyle p=\frac{\text{Red Region}}{\text{Total Region}}[/tex]
Therefore:
[tex]\displaystyle p=\frac{19.5}{16\pi}\approx 0.39=39\%[/tex]
Who got Insta grammm because I really need help with my math assignments I’ll pay you $30 cash app or PayPal if it’s right
Answer:
just post it here im sure i can help w/o pay
Step-by-step explanation:
Answer:
I have Insta gram and I will help you but for free
Find the area of the rectangle, the side lengths are (z+9)(3z+8).
Q. You're working in the sedan section of
Dean's Car Dealership. A customer makes a
down payment of 15% on a new car that costs
$13,450. How much is the down payment?
A. $201.75
B. $2,017.50
C. $269.00
D. $2,690.00
Answer:
B
Step-by-step explanation:
[tex]15%of$13,450=$2,017.50[/tex]%[tex]of13,450=2,017.50[/tex] therefore the down payment is $2,017.50
For this cylinder the radius r = 6.8 inches and the height L - 14.2 inches. Which is the BEST estimate for the volume? (Use TI = 3.14)
Answer:303.19
Step-by-step explanation: HOPE I HELPED
Find the value of ln(-0.379).
Answer:
Undefined
Step-by-step explanation:
To obtain the In(-0.375)
In x = log e x = y
The In is the natural logarithm of a number
To obtain the natural logarithm value of a given number using a calculator :
Simply press the In button followed by the value to obtain the direct value of the number x.
The In of any negative value gives an error output.
The In of x is only defined for values of x greater Than 0; that is ; X > 0
In of negative numbers is undefined
What is the area of the shaded region?
Answer:
17,680 ft²
Step-by-step explanation:
Shaded area = entire shaded rectangle area - unshaded rectangle area - square area
A = 200(100) - 24(30) - 40²
A = 20,000 - 720 - 1600 = 17,680
IS THIS CORRECT ???????
Answer:
yes
Step-by-step explanation:
Answer:Yep
Step-by-step explanation:
I NEED HELP ON A TEST HELP QUICK
There are white blue and red boats at the marina. Two-thirds of the boats in the marina are white, 4/7 of the remaining ...
What can you say about the function that generated the following table of
values?
у
-3
0.125
0.5
-1
2
1
8
3
64
6
6
A. not enough information to answer the question
B. the function has more than one x-intercept
O c. the function has exactly one x-intercept
D. the function has no x-intercepts
The function has exactly one x-intercept.
Option C is the correct answer.
What is a function?
A function has an input and an output.
A function can be one-to-one or onto one.
It simply indicated the relationships between the input and the output.
Example:
f(x) = 2x + 1
f(1) = 2 + 1 = 3
f(2) = 2 x 2 + 1 = 4 + 1 = 5
The outputs of the functions are 3 and 5
The inputs of the function are 1 and 2.
We have,
Based on the table of values provided, we can see that as x increases, y also increases.
This means that the function is increasing function.
Furthermore,
Since the y-values are negative for small x-values and positive for large
x-values, there must be at least one x-intercept where the function changes sign.
So,
We can conclude that the function that generated the table of values has exactly one x-intercept.
Thus,
The function has exactly one x-intercept.
Learn more about functions here:
https://brainly.com/question/28533782
#SPJ7
Help please, i'll give brainliest for the correct answer!
Answer:
I'm pretty sure it's A.
Step-by-step explanation:
.
Find the value of x and the measure of the missing angle labeled A:
Answer:
below with explaination
Step-by-step explanation:
angle A + angle B + angle C = 180
x+x+37+x+67=180
3x+104=180
3x=180-104
3x=76
x=76÷3
x=25.3
angle A = 62.3
Answer:
104 and 90
Step-by-step explanation:
A rectangular prism has a volume of 240cm. It's height measures 8 cm. What is the area of its base
Answer: Base = 90 [tex]cm^{2}[/tex]
Step-by-step explanation:
What is the probability of rolling a 4, 5, or 6 on a die?
Answer:
1/6 chance
Step-by-step explanation:
Write the fraction product of a whole number and a unit fraction.
5/12
Answer:
5*1/12
Step-by-step explanation:
I don't know if this is right but hopefully it is ^^"
pls answer i beg who answers correct get 100 points
Answer:
y=7p+5e
Step-by-step explanation:
I guess, if that is what you are asking
Answer:
If there 3 slices and 4 slices I would say about near 460 calories or higher
Step-by-step explanation:
Calculator
Enter the unknown value that makes this statement true:
25% of O
is 30.
->
-
1
2
3
Answer:
X = 120
Step-by-step explanation:
here's your solution
=> we need to find the number whose 25%
is 30
=>. now , let the number be X
=> solve for X
=>. 25/100*X = 30
=> X = 30*100/25
=> X = 120
hope it helps
How should the decimal point in 52.48 be moved to determine the product 52.48×105 ?
Answer:
2 to the right i belive
Can you please help me with this question:)
Answer:
D
Step-by-step explanation:
Answer:
letter d
Step-by-step explanation:
a loss is negative do a loss of 18 would be -18
What is the correct step to solve this equation?
m + 4 = 10
A. Subtract 4 from both sides
B. Subtract 10 from both sides
C. Add 4 to both sides
D. Add 10 to both sides
50 POINTS... HELP. FIND AC=
9514 1404 393
Answer:
AC = 25
Step-by-step explanation:
The product of the near and far distances from C to the circle is the same for each segment. For segment CD, the near and far distances are the same. So, we have ...
CD² = CB·CA
CA = CD²/CB = 15²/9 = 25
The length AC is 25 units.
_____
It seems possible that in some other versions of this question you might be asked to find x. Then you have ...
AB = AC -BC = 25 -9 = 16
3x +1 = 16 . . . substitute for AB
3x = 15 . . . . . subtract 1
x = 5 . . . . . . . divide by 3
5th grade math. correct answer will be marked brainliest.
Answer:
1, 2, 4, 11, 22, 44.
Step-by-step explanation:
Hope this helps :)
PLS HELP HELP ME WITH a question pls
Step-by-step explanation:
d.
e +e+25=180°{sum of angle of triangle}
2e+25=180°
2e=155
e=155/2
e=77.5°
e.
55°+55°+f=180°{sum of angle of triangle}
f=180-110
f=70°
hope it helps.
Explain how you would use fraction bars to find the quotient of 10/12 divide 4/6. What is the quotient?
Answer:
(10/12) / (4/6) when dividing with fractions, flip what you're dividing by, then multiply
10/12 * 6/4 = 10/8 which reduces to 5/4 or 1 1/4
Help ASAP 45 points
Answer:
fd
Step-by-step explanation:
A study was designed to test whether applying metal tags is detrimental to a penguin. One variable examined is the survival rate 10 years after tagging. The scientists observed that 10 of the 50 metal tagged penguins survived, compared to 18 of the 50 electronic tagged penguins. Construct a confidence interval for the difference in proportion surviving between the metal and electronic tagged penguins (). Let be the proportion of penguins with metal tags that survived and be the proportion of penguins with electronic tags that survived. Round your answers to three decimal places.
Complete question :
A study was designed to test whether applying metal tags is detrimental to a penguin. One variable examined is the survival rate 10 years after tagging. The scientists observed that 10 of the 50 metal tagged penguins survived, compared to 18 of the 50 electronic tagged penguins. Construct a 90% confidence interval for the difference in proportion surviving between the metal and electronic tagged penguins (). Let be the proportion of penguins with metal tags that survived and be the proportion of penguins with electronic tags that survived. Round your answers to three decimal places.
Answer:
(-0.305 ; - 0.015)
Step-by-step explanation:
Sample size, n1 = 50
x1 = 10
n2 = 50
x2 = 18
P1 = x1 / n1 = 10/50 = 0.2
P2 = x2 / n2 = 18 /50 = 0.36
1 - P1 = 0.8 ; 1 - P2 = 0.64
Zcritical at 90% = 1.645
Confidence interval :
(P1 - P2) ± Zcritical * standard error
Standard Error = sqrt[(p1(1-p1))/n1 + (p2(1-p2))/n2]
S.E = sqrt((0.2(0.8))/50 + 0.36(0.64))/50)
S.E = sqrt((0.0032 + 0.004608))
S. E = sqrt(0.007808)
S. E = 0.0883628
(0.2 - 0.36) ± (1.645 * 0.0883628)
-0.16 ± 0.145356806
Lower boundary = - 0.16 - 0.145356806 = −0.305356806
Upper boundary = - 0.16 + 0.145356806 = −0.014643194
(-0.305 ; - 0.015)
A six-week fitness program was designed to decrease the time it takes retired individuals to walk one mile. At the beginning of the program, 20 randomly selected retired individuals were invited to participate, and their times to walk a mile were recorded. After the six-week program, their times to walk a mile were again recorded. Most participants saw little to no improvement in their times to walk one mile; however, a few participants saw drastic improvements in their times to walk one mile. The program director would like to perform a hypothesis test to determine if the program reduces the mean time for retired individuals to walk a mile. Which of the following statements is true?
a. Because there are 40 observations in total, the sample size is large enough to assume that the sampling distribution of the sample mean differences is approximately normal.
b. Because the walk times before and after the program are paired, a hypothesis test is not appropriate.
c. The sampling distribution of sample means can be assumed to be approximately normal because the distribution of the sample data is not skewed.
d. Because the sample size of 20 is less than 30 and the improvements in walk times in the sample data appear to be skewed, the distribution of sample means should not be assumed to be approximately normal.
e. Because the program recruited only retired individuals, the distribution of sample means should not be assumed to be approximately normal.
Answer:
c. The sampling distribution of the sample means can be assumed to be approximately normal because the distribution of the sample data is not skewed
Step-by-step explanation:
From the given data, we have;
The category of the sample = Retired individuals
The number of participants in the sample = 20
The duration of program = six-weeks
The improvement seen by most participants = Little to no improvement
The improvement seen by few participants = Drastic improvement
Therefore, given that the participants are randomly selected and the majority of the participants make the same observation of improvement in the time to walk a mile, we have that, the majority of the outcomes show little difference in walk times after the program, therefore, the distribution of the sample data is not skewed and can be assumed to be approximately normal
5x6x6x6x6x6x62x3x3x3x5x5
Answer:
didid yooooouuu juuuustttttt tyyyypppppeeeee tthhhhhissss iiiiinnnnnn
Step-by-step explanation:
what is thiiiiisssss
Answer:
1627128000 ?
Step-by-step explanation:
Verify the identity.
sin (x + y) - sin (x - y) = 2 cos x sin y
Answer:
Step-by-step explanation:
E
Lisa wants to measure the height of a tree. She sights the top of the tree, using a mirror that is lying flat on the ground. The mirror is 38 ft from the tree, and
Lisa is standing 6.2 ft from the mirror, as shown in the figure. Her eyes are 6 ft above the ground. How tall is the tree? Round your answer to the nearest foot.
(The figure is not drawn to scale.)
Answer:
37
Step-by-step explanation:
38 times 6 divided by 6.2
228/6.2 = 36.774....
Round to meter is 37