Answer:
[tex]sum = \frac{n}{2} (2a + (n - 1)d) \\ = \frac{50}{2} ((2 \times 18) + (50 - 1) \times 3) \\ = 25(36 + 147) \\ = 25 \times 183 \\ sum = 4575[/tex]
Suppose that 10% of the fields in a given agricultural area with about 2,500 fields are infested with the sweet potato white fly. One hundred fields in this area are randomly selected and checked for whitefly.
Required:
a. What is the average number of fields sampled that are infested with whitefly?
b. Within what limits would you expect to find the number of infested fields, with probability approximately 95%?
c. What might you conclude if you found that x=25 fields were infested? Is it possible that one of the characteristics of a binomial experiment is not satisfied in this experiment? Explain.
Answer:
a. 250 fields
b. 220 to 280 fields
c. Fields are not independent
Step-by-step explanation:
a. The average number of fields sampled that are infested with whitefly =
number of fields X Percentage sampled, 10%
= 2500 X 10% = 250 fields
b. Going by the binomial distribution is the square of the standard deviation, divided by (the product of the sample size n, and the probability a and b). While the standard deviation is the square root of the variance
σ = √nab
= √na(1-a) = √2500 X 10% X (1- 10%)
= √225 = 15
Now let's use the empirical rule that says about 95% of the observations are within two standard deviations from the mean since the number of trials is very large
μ - 2σ = 250 - 2(15) = 220
μ + 2σ = 250 + 2(15) = 280
Approximately 220 to 280 fields are expected to be infested going by 95% probability observation
c. Since x=25 is considered small and is not captured within 220 and 280 fields making one of the characteristics of binomial experiment not satisfied which expects each field to be independent. Making fields that are close together more likely to be infected.
Avery spent 10 minutes outside. If
she spent 64 minutes riding her bike,
48 minutes on the trampoline, and the
rest of the time swimming, how many
minutes did Avery spend swimming?
Answer:Cannot be solve how much time did she spend all together but adding it all together would be 122 minutes/ she never went swimming
Step-by-step explanation:
Find the volume of the cone. Round to the nearest tenth.
10 mm
9 mm
Volume:
mm3
Kay enters a cooking contest. As part of the contest, Kay must cook a dish using a randomly assigned meat and vegetable.
The table shows the sample space for the possible meat and vegetable combination she could be assigned.
steak, yams lamb, yams pork, yams tuna, yams salmon, yams
steak, corn lamb, corn pork, corn tuna, corn salmon, corn
steak, beets lamb, beets pork, beets tuna, beets salmon, beets
steak, peas lamb, peas pork, peas tuna, peas salmon, peas
The probability of Kay being assigned either steak or pork as the meat and corn as the vegetable is .
Answer:
2/20 or 1/10
Step-by-step explanation:
this is because there are only 2 options that have steak/pork with corn
Answer:it is 1/10
Step-by-step explanation:
don't ask how im not gonna give an explanation
The half-life of radon-222 (Rn-222) is 3.823 days.How long would it take for three half-lives?
Answer: [tex]7.949\ \text{days}[/tex]
Step-by-step explanation:
Given
The half-life of a sample is [tex]T_{\frac{1}{2}}=3.823\ \text{days}[/tex]
Decay is given by
[tex]A=A_o2^{\dfrac{-t}{T_{\frac{1}{2}}}}[/tex]
After 3 half-lives, one-eight of the sample is left
Insert the values
[tex]\Rightarrow \dfrac{A_o}{8}=A_oe^{\dfrac{-t}{T_{\frac{1}{2}}}}\\\\\Rightarrow e^{\dfrac{t}{T_{\frac{1}{2}}}}=8\\\\\text{Taking log both sides}\\\Rightarrow \dfrac{t}{T_{\frac{1}{2}}}=\ln 8\\\\\Rightarrow t=3.823\times \ln 8\\\\\Rightarrow t=7.944\ \text{days}[/tex]
Answer:
What is this… mortal kombat
Step-by-step explanation:
10. In a survey of 212 people at the local track and field championship, 72% favored the home team
winning
a. Find the margin of error for the survey.
b. Give the 95% confidence interval that is likely to contain the exact percent of all people who
favor the home team winning.
Answer:
a. The margin of error for the survey is of 0.0308 = 3.08%.
b. The 95% confidence interval that is likely to contain the exact percent of all people who favor the home team winning is (65.96%, 78.04%).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].
The margin of error of the survey is:
[tex]M = \sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
The confidence interval can be written as:
[tex]\pi \pm zM[/tex]
In a survey of 212 people at the local track and field championship, 72% favored the home team winning.
This means that [tex]n = 212, \pi = 0.72[/tex]
a. Find the margin of error for the survey.
[tex]M = \sqrt{\frac{0.72*0.28}{212}} = 0.0308[/tex]
The margin of error for the survey is of 0.0308 = 3.08%.
b. Give the 95% confidence interval that is likely to contain the exact percent of all people who favor the home team winning.
95% confidence level
So [tex]\alpha = 0.05[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].
Lower bound:
[tex]\pi - zM = 0.72 - 1.96*0.0308 = 0.6596[/tex]
Upper bound:
[tex]\pi + zM = 0.72 + 1.96*0.0308 = 0.7804[/tex]
As percent:
0.6596*100% = 65.96%
0.7804*100% = 78.04%.
The 95% confidence interval that is likely to contain the exact percent of all people who favor the home team winning is (65.96%, 78.04%).
Match terms to definitions
A. Statistic.
B. Null hypothesis.
C. Slope of the least-squares line
D. Population
E. p-value.
F. Coefficient of Determination r2begin mathsize 12px style r squared end style -
G. z-score
H. Parameter
I. Sampling distribution
J. Sample
1. Probability, assuming null hypothesis is true, that test statistic will take a value as extreme as observed.
2. All objects or individuals of interest.
3. Probability distribution of a sample statistic based on all possible simple random samples of the same size from the same population.
4. Ratio of explained variation over total variation in y that can be explained by the regression equation using x as the explanatory variable.
5. Some individuals or objects of interest.
6. A numerical measure that describes an aspect of a sample.
7. Distance from mean in terms of standard deviation units.
8. A claim about a population parameter.
9. A numerical measure that describes an aspect of a population.
10. Marginal change of the response variable.
Answer:
A. Statistic = A numerical measure that describes an aspect of a sample.
B.) Null hypothesis = A claim about a population parameter.
C.) Slope of the least square line = Marginal change in response variable.
D.) Population = All Objects or individual of interest
E.) P - value = Probability, assuming null hypothesis is true, that test statistic will take a value as extreme as observed.
F.) Coefficient of determination = Ratio of explained variation over total variation in y that can be explained by the regression equation using x as the explanatory variable.
G.) Z score = Distance from mean in terms of standard deviation units.
H.) Parameter = A numerical measure that describes an aspect of a population.
I.) Sampling distribution = Probability distribution of a sample statistic
J. Sample = Some individuals or objects of interest
Step-by-step explanation:
Answer is Explanatory
an area that is 21 metre wide and 9 metre long is divided evenly into squares . what the greatest possible side length the squares that the area can be evenly divided into
Answer:
47 squares
Step-by-step explanation:
Looking at your question was quite confusing.
So, I'll assume that you're looking for the amount of squares that can fit within the specified area.
To find area: we would do A = L x W
So, our values are 21W and 9L.
Plug it in.
A = 21 x 9
A = 189 square meters
Then, we would find the number of squares that could fit in the area.
A square meter is a square with a side length of 1 meter on each side.
So, 1 x 4 = 4
Divide 189 by 4.
189/4 = 47.25
1/4 is the remainder.
So, our total is 47 squares.
Do please, tell me if I did it incorrectly, since the context is quite vague.
A giant tortoise can travel 0.19 miles in 1 hour. At this rate, how long would it take the tortoise to travel 1 mile?
Answer:
5.26 hours or 315.6 minutes
Step-by-step explanation:
If he travels 0.19 miles in 1 hour
Then 1 mile is traveled (1x1)/0.19
5.26 approx. hours or 5.26 x 60 mins = 315.6.
8) Tim earns $15.00 per hour at his job. Last week he earned $800. a) Write an equation that can be used to determine the number of hours that he worked last week. b) What is the number of hours he worked? T
Answer:
a= 800/15
b=53 hours round to nearest
Step-by-step explanation:
Select ALL ordered pairs that are located in the first quadrant of the coordinate plane.
A (-3,8)
B (9,-7)
C (5,4)
D (2,6)
Answer:
C, D
Step-by-step explanation:
in the first coordinate plane, both numbers in a coordinate must be positive
A binomial experiment is given. Determine whether you can use a normal distribution to approximate the binomial distribution. If you can, find the mean and standard deviation. If you cannot, explain why. A survey of U.S. adults found that 37% have been to court. You randomly select 30 U.S. adults and ask them whether they have been to court.
Answer:
Since both [tex]np \geq 10[/tex] and [tex]n(1-p) \geq 10[/tex], you can use a normal distribution to approximate the binomial distribution.
The mean is of 11.1 and the standard deviation is of 2.64.
Step-by-step explanation:
Binomial probability distribution
Probability of exactly x successes on n repeated trials, with p probability.
The expected value of the binomial distribution is:
[tex]E(X) = np[/tex]
The standard deviation of the binomial distribution is:
[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]
Using the normal distribution to approximate the binomial distribution.
This is possible if:
[tex]np \geq 10, n(1-p) \geq 10[/tex]
A survey of U.S. adults found that 37% have been to court. You randomly select 30 U.S.
This means that [tex]p = 0.37, n = 30[/tex]
Test if it is possible:
[tex]np = 30*0.37 = 11.1[/tex]
[tex]n(1-p) = 30*0.63 = 18.9[/tex]
Since both [tex]np \geq 10[/tex] and [tex]n(1-p) \geq 10[/tex], you can use a normal distribution to approximate the binomial distribution.
Mean and standard deviation:
[tex]E(X) = np = 30*0.37 = 11.1[/tex]
[tex]\sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{30*0.37*0.63} = 2.64[/tex]
The mean is of 11.1 and the standard deviation is of 2.64.
IF ITS RIGHT ILL MARK BRAINLIEST
Answer:
Answer is 12
Step-by-step explanation:
angle BCF+angle CFE=180(being co-interior angle)
4x+11x=180
15x=180
x=180/15
x=12
plss help!!sorry if i asked alot
Answer:
[tex] \frac{2 }{3} [/tex]
Step-by-step explanation:
Formula is
y=mx+c So,2by 3 is m and x is there and 2 at last is c .
answer is 2 by 3
stan bought 5lbs of raisins at $3.55/lb . if he wanted to but 4 more pounds of a different kind of raisins to make the average price per pound equals to $3.23 what price should he pay for the additional 4lb?
Answer:
$2.83
Step-by-step explanation:
5lb × $3.55/lb + 4lb × x = 9 lb ×$3.23/lb
$17.75 + 4lb(x) = $29.07
-$17.75. -$17.75
4lb(x) = $11.32
___________
4lb. 4lb
x = $2.83
which graph is the graph of f(x) = 2 + 2?
A stove heats food by adding _______ to the food.
QUICK PLEASE!
What is the absolute value of -4?
Answer:
4
Step-by-step explanation:
the absolute value is the distance a number is from zero.
Answer:
Step-by-step explanation:
The absolute value of 4 is 4 and –3 is 3. Subtract the smaller number from the larger and you get 4 – 3 = 1. The larger absolute value in the equation was 4 or a positive number so you give the result a positive result. Therefore, the result of 4 + –3 = 1.
hope that helped, have a nice!
eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeebrainliest
Answer:
1/3
Step-by-step explanation:
Divide the numerator and denominator by 6.
6/18 = 1/3
There are 30 students in a seventh grade class who attend after school activities.
• Of the students, 5 take music lessons.
3
• Of the students, 5 play a sport.
• The remaining students go to drama club.
How many students go to drama club after school?
O A. 11 students
OB.
23 students
O C.
7 students
OD
15 students
Answer:
7 students.
Step-by-step explanation:
1/6 of 30 is 5
3/5 of 30 is 18
18+5=23
30-23=7
The parks department plans to cover a rectangular field
in a park with grass and must find the area of the field.
The field is 10 m longer than it is wide. The width of the
field is 25 m. What is the area to be seeded?
ASAP rn
Answer: 875 m²
Step-by-step explanation:
show correct answers only!! i need asap!!
Answer:
11 1/2 aka D
Step-by-step explanation:
add 7 and 4 which is 11, then add 1/4 and 1/4 which is 1/2
Answer:
D.) 11 1/2
Step-by-step explanation:
50 POINTS !!
PLEASE HELP !! ILL GIVE BRAINLIEST TO THE RIGHT ANSWERS.
Clara goes miniature golfing. She pays $7.50 for
admission ticket and $6.25 for each round she golfs.
The total amount Clara pays for admission and the
number of rounds she golfs is $26.25. Which equation
can be used to determine the number of rounds, x, that
Clara golfs?
A) 6.25x + 7.50 = 26.50
B 6.25x = 7.50 = 26.25
C) 7.50x + 6.25 = 26.25
D) 7.50x - 6.25 = 26.25
Answer:A
Step-by-step explanation:
She has to pay 7.50 for admission and golf is 6.25 each round. We don’t know how many rounds she golfs so it will be 6.25x.
If x varies inversely as v, and x = 35 when v = 3, find x when v = 15
Answer:
x = 7
Step-by-step explanation:
Given that,
x varies inversely as v.
When v = 3, x = 35.
We need to find x when v = 15
ATQ,
[tex]x=\dfrac{k}{v}[/tex]
Put v = 3, x = 35,
[tex]k=3\times 35\\\\k=105[/tex]
Now put v = 15 and k = 105
[tex]x=\dfrac{105}{15}\\\\x=7[/tex]
So, the required value of x is equal to 7.
Pls help ill give u brainlest!! 40 points
Hakeem owns seven less than 3/5 the number of DVDs that Manuel owns. Hakeem owns 20 DVDs. How many DVDs does Manuel own? Show your work.
Answer:
Manuel owns 5 DVDS
Step-by-step explanation:
3/5 = 12/20
12 - 7 = 5
you watch seven deadly sins?
Please answer for brainliest [answer number 2]
Answer:
4
Step-by-step explanation:
PLZ HURRY GOT 10 MINS LEFT
Answer:
6 units
Step-by-step explanation:
Both units lie on the -5 x-axis, so you only have to look at the difference in the y-axis. Going from -2 to -8 is a 6 unit difference.
Hope this helps :)
3
47. Matt and Carla each spent $100 at the mall. Together they bought five sweaters and two pairs of pants
expressions
represent
the total cost of their purchases
A 100 - 5s
B. 100 - 2p
C. 5 + 2p
D. 7sp
Answer:
The total cost of their purchases is 5s + 2p = 100
Step-by-step explanation:
I am going to say that:
The price of a sweater is s.
The price of a pair of pants is p.
Matt and Carla each spent $100 at the mall. Together they bought five sweaters and two pairs of pants
5 sweaters: 5s
2 pairs of pants: 2p
Total:
5s + 2p
Since the total is 100:
5s + 2p = 100
The total cost of their purchases is 5s + 2p = 100
What is the area of the sector for the following circle? Round your answer to 4 decimal places. *
Answer:
13.0833 ft²
Step-by-step explanation:
From the question given above, the following data were obtained:
Radius (r) = 5 ft
Angle sustained by the sector (θ) = 360 – 300
= 60°
Pi (π) = 3.14
Area of sector (A) =?
The area of the sector can be obtained as follow:
A = θ/360 × πr²
A = 60/360 × 3.14 × 5²
A = 1/6 × 3.14 × 25
A = 1/6 × 78.5
A = 78.5/6
A = 13.0833 ft²
Thus, the area of the sector is 13.0833 ft²
Step-by-step explanation:
The angle of the minor sector will be ,
> 360 - 300 = 60° .
Area of sector :-
> Area = ∅ / 360 × πr²
> A = 60/360 × 3.14 × 5ft²
> A = 13.09 ft²