Answer:
c. 13.5 cm
Step-by-step explanation:
In the right triangle formed by the main sail.
Using the trigonometric function
[tex]\tan \theta =\dfrac{\text{Opposite}}{\text{Adjacent}} \\\tan 52^\circ =\dfrac{x}{9} \\x=9 \times \tan 52^\circ\\x=11.52$ cm[/tex]
Therefore:
Height of the mast = 2+11.5=13.5 cm
The height of the mast is 13.5 cm.
The concern of a study by Beynnon et al. (A-4) were nine subjects with chronic anterior cruciate ligamenttears. One of the variables of interest was the laxity of the anteroposterior, where higher values indicate more knee instability. The researchers found that among subjects with ACL-deficient knees, the mean laxity value was 17.4mm with a standard deviation of 4.3mm.
(a) What is the estimated standard error of the mean?
(b) Construct the 99 percent confidence interval for the mean of the population from which the nine subjects may be presumed to be a random sample.
(c) What is the precision of the estimate?
(d) What assumptions are necessary for the validity of the conidence interval you constructed?
Answer:
a) Standard error of the mean = 1.433 mm
b) 99% confidence interval = (12.6, 22.2)
c) The precision of the estimate = 4 816
d) The assumptions that are necessary for the validity of the conidence interval constructed include
- The sample must be a random sample extracted from the population, with each variable in the sample independent from one another.
- The sample must be a normal distribution sample or approximate a normal distribution and the best way to establish this is when the population distribution where the sample was extracted from is normal or approximately normal.
Step-by-step explanation:
a) Standard error of the mean is given as
σₓ = (σ/√n)
σ = Sample standard deviation = 4.3 mm
n = sample size = 9
σₓ = (4.3/√9) = 1.433 mm
b) Confidence Interval for the population mean is basically an interval of range of values where the true population mean can be found with a certain level of confidence.
Mathematically,
Confidence Interval = (Sample mean) ± (Margin of error)
Sample Mean = 17.4 mm
Margin of Error is the width of the confidence interval about the mean.
It is given mathematically as,
Margin of Error = (Critical value) × (standard Error of the mean)
Critical value will be obtained using the t-distribution. This is because there is no information provided for the population mean and standard deviation.
To find the critical value from the t-tables, we first find the degree of freedom and the significance level.
Degree of freedom = df = n - 1 = 9 - 1 = 8.
Significance level for 99% confidence interval
(100% - 99%)/2 = 0.5% = 0.005
t (0.005, 8) = 3.36 (from the t-tables)
Standard error of the mean = 1.433 mm
99% Confidence Interval = (Sample mean) ± [(Critical value) × (standard Error of the mean)]
CI = 17.4 ± (3.36 × 1.433)
CI = 17.4 ± 4.816
99% CI = (12.584, 22.216)
One crate orė
99% Confidence interval = (12.584, 22.216)
c) The precision of the estimate is gven as the length of the, margin of error of the confidence interval. The precision of the estimate = 4.816
d) They include
- The sample must be a random sample extracted from the population, with each variable in the sample independent from one another.
- The sample must be a normal distribution sample or approximate a normal distribution and the best way to establish this is when the population distribution where the sample was extracted from is normal or approximately normal.
Hope this Helps!!!
The driver of a car traveling at 42 ft/sec suddenly applies the brakes. The position of the car is s equals 42 t minus 3 t squared comma t seconds after the driver applies the brakes. How far does the car go before coming to a stop?
Answer:
after 7 seconds the driver applied the brakes to stop the car.
Step-by-step explanation:
Given:
The position of the car s(t)=[tex]42t-3t^2[/tex]
∴Speed of the car =[tex]\frac{ds}{dt}=\frac{d(42t-3t^2)}{dt}=42-6t[/tex]
When car stopped the speed of car=0
[tex]\Rightarrow42-6t=0\\\Rightarrow6t=42\\\Rightarrow\ t=7[/tex]
Therefore, after 7 seconds the driver applied the brakes to stop the car.
There are 11 students in our Science class left to give their presentations. Today we will have time for 6 presentations. How many different ways can the teacher choose the presenters?
Answer:
He has 2,772 ways
Step-by-step explanation:
Hello,
the teacher has to choose 6 students and there are 11 students in total.
When he chooses the first student he has 11 choices
if he has to choose 1 students he has 11 ways to do it
then for the second one he has 11-1=10 choices
if he has to choose 2 students he has (11*10)/2 ways to do it (we do not count the duplicate - for instance if he chooses Steve and then Nils or Nils and then Steve this is only one group (Steve, Nils) we do not care of the order)
Then for the third student he has 10-1=9 choices
if he has to choose 3 students he has (11*10*9)/(2*3) ways to do it (we do not take into account the order of ppl in the group)
and so on and so forth
...
if he has to choose 6 students he has (11*10*9*8*7*6)/(2*3*4*5)
so he has 2,772 ways
Answer:
C. 462 is correct. I did the test.
Step-by-step explanation:
Three hunters X, Y and Z aim at a bird on top of a tree. Their individual probabilities of killing the bird are 3/5, 2/3 and 5/6 respectively.
Find the probability that
i. Only X and Y kill the bird
ii. Only two of them kill the bird
iii. Only Z kill the bird
iv. Only one of them kill the bird
v. None of them kill the bird
vi. All of them kill the bird
Answer:
i. Only X and Y kill the bird = 2/5
ii. Only two of them kill the bird= 0.11
iii. Only Z kill the bird= 5/6
iv. Only one of them kill the bird= 1/3
v. None of them kill the bird= 0
vi. All of them kill the bird= 1
Step-by-step explanation:
Probability of x= 3/5
Probability of y = 2/3
Probability of z = 5/6
i. Only X and Y kill the bird
= 3/5 * 2/3
= 2/5
ii. Only two of them kill the bird
=Either x and y or x and z or y and z
= 2/5 or 1/2 or 5/9
= 0.111
iii. Only Z kill the bird
= 5/6
iv. Only one of them kill the bird
= 3/5 or 2/3 or 5/6
= 1/3
v. None of them kill the bird
0
vi. All of them kill the bird
1
Write the rectangular equation (x+5) 2 + y 2 = 25 in polar form.
Answer:
r = -10*cos(t)
Step-by-step explanation:
To write the rectangular equation in polar form we need to replace x and y by:
[tex]x=r*cos(t)\\y=r*sin(t)[/tex]
Replacing on the original equation, we get:
[tex](x+5)^2+y^2=25\\x^2+10x+25+y^2=25\\(r*cos(t))^2+10*(r*cos(t))+25+(r*sin(t))^2=25[/tex]
Using the identity [tex]sin^2(t)+cos^2(t)=1[/tex] and solving for r, we get that the polar form of the equation is:
[tex](r*cos(t))^2+10*(r*cos(t))+25+(r*sin(t))^2=25\\r^2cos^2(t)+10rcos(t)+r^2sin^2(t)=0\\r^2cos^2(t)+r^2sin^2(t)=-10rcos(t)\\r^2(cos^2(t)+sin^2(t))=-10rcos(t)\\r^2=-10rcos(t)\\\\r=-10cos(t)[/tex]
What is the distance between the following points?
Answer:
D. d = [tex]\sqrt{58}[/tex]
Step-by-step explanation:
Use the distance formula: d = [tex]\sqrt{(x2 - x1)^{2}+ (y2 - y1)^{2} }[/tex]
The two points are (6, -2) and (3, -9)
Plug the values into the formula:
d = [tex]\sqrt{(3 - 6)^{2}+ (-9 + 2)^{2} }[/tex]
Simplify
d = [tex]\sqrt{(-3)^{2}+ (-7)^{2} }[/tex]
d = [tex]\sqrt{9+ 49 }[/tex]
d = [tex]\sqrt{58}[/tex]
I hope this helps :))
Working together Wayne and his son Garth can mow the lawn in 30 min, but if Wayne mow the lawn alone then it takes 1h 15min. Find how long does it take for Garth to mow their lawn if he does it alone.
Answer:
105
Step-by-step explanation:
1h and 15 minutes is 75 minutes so
30+75=
70+30=100
100+5=105
Answer:
105
Step-by-step explanation:
I copied the other dude
Which of the following is NOT a solution to 2x+3y=12? A. (5,-3) B. (9,-2) C. (0,4) D. (6,0)
Answer:
B
Step-by-step explanation
As an estimation we are told £3 is €4.
Convert €48 to pounds.
Answer: £36
Step-by-step explanation:
4 Euros = £3
48 Euros (4x12) = £36 (3x12)
Answer:
£ 36.00
Step-by-step explanation:
£ 3 = € 4
Divide both sides by 4.
£ 3/4 = € 1
1 euro is 3/4 pound.
48 × 3/4 = 36
£ 36 = € 48
48 pounds is 36 euros.
What is the ratio 16 : 12 in its simplest form?
Answer:
4 : 3
Step-by-step explanation:
16 : 12 can be simplified by 4 to get 4 : 3
Answer:
[tex]4:3[/tex]
Step-by-step explanation:
[tex]16 : 12[/tex]
The common highest factor of the ratio is 4.
Simplify the ratio.
[tex]16 \div 4:12 \div 4[/tex]
[tex]4:3[/tex]
A) estimate the value of 9.9^2 x 1.79 B)estimate the value of V^(square root) 97.5/1.96 Thanks.
Answer:
Below in bold.
Step-by-step explanation:
A). 9.9^2 is close to 10^2 = 100
Round 1.79 to 1.8
So an estimate is 1.8 * 100
= 180.
B). √97.5 / 1.96
( I am assuming that the square root is of 97.5 only).
is approximately equal to √100 / 2
= 10/2
= 5.
Which of the following statements are equivalent to the statement "Every integer has an additive inverse" NOTE: (The additive inverse of a number x is the number that, when added to x, yields zero. Example: the additive inverse of 5 is -5, since 5+-5 = 0) Integers are{ ... -3, -2,-1,0, 1, 2, 3, ...} All integers have additive inverses. A. There exists a number x such that x is the additive inverse of all integers.B. All integers have additive inverses.C. If x is an integer, then x has an additive inverse.D. Given an integer x, there exists a y such that y is the additive inverse of x.E. If x has an additive inverse, then x is an integer.
Answer:
B, C and D
Step-by-step explanation:
Given:
Statement: "Every integer has an additive inverse"
To find: statement that is equivalent to the given statement
Solution:
For any integer x, if [tex]x+y=0[/tex] then y is the additive inverse of x.
Here, 0 is the additive identity.
Statements ''All integers have additive inverses '', '' If x is an integer, then x has an additive inverse'' and ''Given an integer x, there exists a y such that y is the additive inverse of x'' are equivalent to the given statement "Every integer has an additive inverse".
Does anybody know why these are wrong?
Answer:
They aren't wrong. The program is.
Step-by-step explanation:
The numbers you entered are the answers that matches the correct answers. It is a program error.
Estimate the area of the circle equal three decimal 14 round to the nearest hundredth if necessary9
Answer:
49π m² or 153.94 m²
Step-by-step explanation:
Area of a circle: A = πr²
We are given r as 7, so simply plug it in
A = π(7)^2
A = 49π m²
The National Association of Realtors estimates that 23% of all homes purchased in 2004 were consideredinvestment properties. If a sample of 800 homes sold in 2004 is obtained what is the probability that between175 and 200 homes are going to be used as investment property
Answer:
0.9099
Step-by-step explanation:
1) =
=
200
800
= .25
2) Identify = . = .23
3) Find the z-value.
=
−
(1−)
=
.25−.23
.23(1−.23)
800
= 1.34
4) The probability is 0.9099.
Q2 (i). A line “t” is parallel to 3y = 6x + 9. Find the slope of this line “t”. (ii) Another line “r” is perpendicular to the line 3y = 6x + 9. Find the gradient of the line “r”. plz can anyone tell me by doing the practice on the copy I will be thankful
Answer: 6 and -1/6
Step-by-step explanation:
solving for y. You get y = -2x +5, so the slope is –2. Perpendicular lines have opposite-reciprocal slopes, so the slope of the line we want to find is 1/2. Plugging in the point given into the equation y = 1/2x + b and solving for b, we get b = 6.
Answer:
1) 2
2) -1/2
Step-by-step explanation:
1) 3y= 6x+9
y= 2x+3
Slope is 2
Parallel line "t" has the same slope, it will have equation:
y= 2x+b
2) y =2x+3
Perpendicular line"r" has a slope opposite-reciprocal to this, so the slope will be -1/2, the equation for line"r" is:
y= -1/2x +b
The gradient of the line is same as slope and it is -1/2 for line"r"
A grocery store bought ice cream for $2.80 per half gallon and stored it in two freezers. During the night, one freezer malfunctioned and ruined 12 half gallons. If the remaining ice cream is sold for $3.96 per half gallon, how many half gallons did the store buy if they made a profit of $66.16?
Steps:
Add 47.52 to both sides
Divide both sides by 1.16
x= 98
Description:
The first step is to add 47.52 to both sides then simplify it then divide the both sides by 1.16. And your answer will equal as x=98.
Answer: x= 98
Please mark brainliest
Hope this helps.
How many different ways can the letters of "kissing" be arranged?
Answer:1260
Step-by-step explanation:
Kissing has 7 letters, and there are 2 paris of the same letter.
[tex]\frac{7!}{2!2!}[/tex] = [tex]\frac{7*6*5*4*3*2*1}{4}[/tex]= 1260
2÷3 ? 4÷5 A. > B. < C. =
Answer: B
Step-by-step explanation:
To know the inequality, we can divide the numbers on each side to see what belongs in the middle.
0.67 ? 0.80
We can see that 0.67 is smaller than 0.8. Therefore, the inequality should be <.
0.67<0.8
In a pizza takeout restaurant, the following probability distribution was obtained for the number of toppings ordered on a large pizza. Find the mean and standard deviation for the random variable.
Answer:
The random variable (number of toppings ordered on a large pizza) has a mean of 1.14 and a standard deviation of 1.04.
Step-by-step explanation:
The question is incomplete:
The probability distribution is:
x P(x)
0 0.30
1 0.40
2 0.20
3 0.06
4 0.04
The mean can be calculated as:
[tex]M=\sum p_iX_i=0.3\cdot 0+0.4\cdot 1+0.2\cdot 2+0.06\cdot 3+0.04\cdot 4\\\\M=0+0.4+0.4+0.18+0.16\\\\M=1.14[/tex]
(pi is the probability of each class, Xi is the number of topping in each class)
The standard deviation is calculated as:
[tex]s=\sqrt{\sum p_i(X_i-M)^2}\\\\s=\sqrt{0.3(0-1.14)^2+0.4(1-1.14)^2+0.2(2-1.14)^2+0.06(3-1.14)^2+0.04(4-1.14)^2}\\\\s=\sqrt{0.3(-1.14)^2+0.4(-0.14)^2+0.2(0.86)^2+0.06(1.86)^2+0.04(2.86)^2}\\\\ s=\sqrt{0.3(1.2996)+0.4(0.0196)+0.2(0.7396)+0.06(3.4596)+0.04(8.1796)}\\\\s=\sqrt{0.3899+0.0078+0.1479+0.2076+0.3272}\\\\ s=\sqrt{ 1.0804 }\\\\s\approx 1.04[/tex]
Answer:
mean: 1.14; standard deviation: 1.04
Step-by-step explanation:
Which of the following verified the triangle COW is similar to triangle PIG? Ignore the answer I filled in I didn’t meant to pick that one.
Answer:
D. SSS theorem
Step-by-step explanation:
The triangles have similarity by 3 sides:
4/12=5/15=7/21So the answer is SSS
helpp i cant understand this question
A box is 24 inches long, 10 inches wide, and 10 inches deep. About how many cubic feet is the box?
Answer:
1.3888888 ft^3
Step-by-step explanation:
We need to find the volume
V = l*w*h
V = 24*10*10
V =2400 in^3
We want cubic ft
Divide by 12 for each foot
12*12*12 = 1728 ft^3
2400/1728 =1.3888888 ft^3
Answer:
[tex] = 1.388889 {ft}^{3} [/tex]
Step-by-step explanation:
[tex]v = whl \\ = 10 \times 24 \times 10 \\ = 2400 {in}^{3} [/tex]
we know that,
[tex]1 \: \: in = 0.833333ft \\ x = 2400 \\ use \: \: cross \: \: \: multipication \\ 2400 = 0.833333x \\ \frac{2400}{0.833333} = \frac{0.833333x}{0.833333} \\ x = 1.388889 {ft}^{3} [/tex]
hope this helps
brainliest appreciated
good luck! have a nice day!
Evelyn pets the box with 1 inch cubes with represents does not show how evelyn can’t find the volume of the box
Question Correction
Evelyn packed this box with 1 inch cubes. Which expression does not show how Evelyn can find the volume of the box?
(A)6+6+6+6+6+6 (B) 2 X 3 X 6 (C) 2 + 3 + 6 (D) 6 X 6Answer:
(C) 2 + 3 + 6
Step-By-Step Explanation
In the diagram,
Height = 6 Units Length =2 Units Width =3 UnitsVolume = Height X Length X Width
= 6 X 2 X 3
=36 cubic units
Consider the options:
(A)6+6+6+6+6+6 =36 cubic units
(B) 2 X 3 X 6 =36 cubic units
(C) 2 + 3 + 6 = 11 cubic units
(D) 6 X 6 =36 cubic units
Out of the option, that which is not equivalent to 36 cubic units is:
(C) 2+3+6
Therefore, it does not show how Evelyn can find the volume of the box.
Answer:
2+3+6
Step-by-step explanation:
i just did it
What is the product of the polynomials below?
(3x2 - 2x - 3)(5x2 + 4x + 5)
Answer:
15x^4+2x^3-8x^2+2x-15
Step-by-step explanation:
3. How many different arrangements can be made with the letters in the word
POWER?
O A 100
B 25
OC 20
OD 120
Answer:
D. 120
Step-by-step explanation:
Array formula: A (n, p) = n! / (n -p)!
At where:
n = Total number of elements in the set.
p = Quantity of elements per arrangement
A (5.5) = 5! / (5-5)! = (5x4x3x2x1) / 0!
By definition: 0! = 1
Then: 120/1 = 120
You want to obtain a sample to estimate a population proportion. At this point in time, you have no reasonable estimate for the population proportion. You would like to be 90% confident that you esimate is within 2.5% of the true population proportion. How large of a sample size is required
Answer:
[tex]n=\frac{0.5(1-0.5)}{(\frac{0.025}{1.64})^2}=1075.84[/tex]
And rounded up we have that n=1076
Step-by-step explanation:
Information given
[tex]ME= 0.025[/tex] represent the desired margin of error
Solution
In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 90% of confidence, our significance level would be given by and . And the critical value would be given by:
[tex]t_{\alpha/2}=-1.64, t_{1-\alpha/2}=1.64[/tex]
The margin of error for the proportion interval is given by this formula:
[tex] ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}[/tex] (a)
We can assume that the best estimate for the true proportion is [tex]\hat p=0.5[/tex]. And on this case we have that [tex]ME =\pm 0.025[/tex] and we are interested in order to find the value of n, if we solve n from equation (a) we got:
[tex]n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}[/tex] (b)
And replacing into equation (b) the values from part a we got:
[tex]n=\frac{0.5(1-0.5)}{(\frac{0.025}{1.64})^2}=1075.84[/tex]
And rounded up we have that n=1076
What is the square root of 28
Answer:5. 291503
Step-by-step explanation:
√28
2√7
5. 291503
Let $r$ and $s$ be the roots of $3x^2 + 4x + 12 = 0.$ Find $r^2 + s^2.$ Pls help.
Answer:
-56/9
Step-by-step explanation:
By Vieta's formulas,
$r + s = -\frac{4}{3}$ and $rs = \frac{12}{3} = 4.$ Squaring the equation $r + s = -\frac{4}{3},$ we get
$r^2 + 2rs + s^2 = \frac{16}{9}.$ Therefore,
$r^2 + s^2 = \frac{16}{9} - 2rs = \frac{16}{9} - 2 \cdot 4 = -\frac{56}{9}}$
The Venn diagram below is used for showing odd numbers and prime numbers.
Place the numbers 1, 2, 3, 4 and 5 in the Venn diagram.
Answer:
See attached
Step-by-step explanation:
Given the numbers 1,2,3,4 and 5
Odd Numbers =1, 3 and 5Prime Numbers = 2, 3 and 5Let O be the event that the number is Odd
Let E be the event that the number is Prime
Then the intersection of Odd and Prime Numbers: [tex]O \cap P =\{3,5\}[/tex]
Since 4 is neither odd nor prime, we place it outside of the two circles.
See the attached diagram for the required Venn diagram.