Answer:
(a) The probability that the average of the draws will be in the range 80 to 120 is 1.
(b) The probability that the average of the draws will be in the range 99 to 101 is 0.6827.
Step-by-step explanation:
According to the Central Limit Theorem if we have an unknown population with mean μ and standard deviation σ and appropriately huge random samples (n > 30) are selected from the population with replacement, then the distribution of the sample mean will be approximately normally distributed.
Then, the mean of the sample means is given by,
[tex]\mu_{\bar x}=\mu[/tex]
And the standard deviation of the sample means is given by,
[tex]\sigma_{\bar x}=\frac{\sigma}{\sqrt{n}}[/tex]
As the sample selected is quite large, i.e. n = 400 > 30, then the sampling distribution of sample means will be approximately normally distributed.
Compute the mean and standard deviation of sample mean as follows:
[tex]\mu_{\bar x}=\mu=100\\\\\sigma_{\bar x}=\frac{\sigma}{\sqrt{n}}=\frac{20}{\sqrt{400}}=1[/tex]
So, [tex]\bar X\sim N(100, 1)[/tex]
(a)
Compute the probability that the average of the draws will be in the range 80 to 120 as follows:
[tex]P(80<\bar X<120)=P(\frac{80-100}{1}<\frac{\bar X-\mu_{\bar x}}{\sigma_{\bar x}}<\frac{120-100}{1})[/tex]
[tex]=P(-20<Z<20)\\\\=P(Z<20)-P(Z<-20)\\\\=(\approx1)-(\approx0)\\\\=1[/tex]
Thus, the probability that the average of the draws will be in the range 80 to 120 is 1.
(b)
Compute the probability that the average of the draws will be in the range 99 to 101 as follows:
[tex]P(99<\bar X<101)=P(\frac{99-100}{1}<\frac{\bar X-\mu_{\bar x}}{\sigma_{\bar x}}<\frac{101-100}{1})[/tex]
[tex]=P(-1<Z<1)\\\\=P(Z<1)-P(Z<-1)\\\\=0.6827[/tex]
Thus, the probability that the average of the draws will be in the range 99 to 101 is 0.6827.
Starting from an airport, an airplane flies 290 miles east and then 290 miles northwest. How far, in miles, from the airport is the plane? (Round your answer to the nearest mile.)
Answer:
The airplane is 222 miles far from the airport.
Step-by-step explanation:
After a careful reading of the statement, distances can be described in a vectorial way. A vector is represented by a magnitude and direction. That is:
Airplane flies 290 miles (east) (290 km with an angle of 0º)
[tex]\vec r_{A} = (290\,mi)\cdot i[/tex]
Airplane flies 290 miles (northwest) (290 km with and angle of 135º)
[tex]\vec r_{B} = [(290\,mi)\cdot \cos 135^{\circ}]\cdot i + [(290\,mi)\cdot \sin 135^{\circ}]\cdot j[/tex]
The resultant vector is equal to the sum of the two vectors:
[tex]\vec r_{C} = \vec r_{A} + \vec r_{B}[/tex]
[tex]\vec r_{C} = \{(290\,mi) + \left[(290\,mi)\cdot \cos 135^{\circ}\right]\}\cdot i + \left[(290\,mi)\cdot \sin 135^{\circ}\right]\cdot j[/tex]
[tex]\vec r_{C} = (84.939\,mi)\cdot i + (205.061\,mi)\cdot j[/tex]
The magnitude of the final distance of the airplane from the airport is obtained by the Pythagorean Theorem:
[tex]\|\vec r_{C}\|=\sqrt{(84.939\,mi)^{2}+(205.061\,mi)^{2}}[/tex]
[tex]\|\vec r_{C}\| = 221.956\,mi[/tex]
The airplane is 222 miles far from the airport.
To decrease a number by 40%, what do we multiply by???
Answer:
Step-by-step explanation:
to decrease a number by 40% i would do
100% = number you got
50% divide by 2
10%= dived 100% number by 10 then take the 10% away from the 50% to get 40%
then take the 40% away from the 100%
hope this helps :)
I WILL GIVE BRAINLIEST!!!! Calculate cos M if a= 4, b= 12.5, c= 13.1244 **Round your answer up to four decimal places.
Answer:
cosM ≈ 0.3048
Step-by-step explanation:
remember SOH CAH TOA = sine: opposite/hypotenuse; cosine: adjacent/hypotenuse; tangent: opposite/adjacent
cos = CAH
cosM= a / c
cosM = 4.0 / 13.1244
cosM = 0.30477
cosM ≈ 0.3048
4xy-3x+8y2-6y 8y-6 please help someone thank you
Answer:
x=6, y=2.5
Step-by-step explanation:
A printer can print 12 pages in 9 seconds. What is the closest estimate of the number of pages it can print in one minute?
Answer:
80 pages
Step-by-step explanation:
Let's use a ratio to solve:
pages : seconds
12 : 9
4 : 3
[tex]p[/tex] : 60
It would seem that [tex]p[/tex] would equal 80. The printer can print 80 pages in 60 seconds or one minute.
I need help with this please answer
Answer:
B. [tex]1\frac{1}{7}[/tex]
Step-by-step explanation:
[tex]-9\frac{2}{7}[/tex]=[tex]-\frac{65}{7}[/tex]
[tex]-10\frac{3}{7}[/tex]=[tex]-\frac{73}{7}[/tex]
[tex]-\frac{65}{7}[/tex]-([tex]-\frac{73}{7}[/tex])=8/7
8/7=[tex]1\frac{1}{7}[/tex]
Hope this helped!!!
need help a s a p HURRYYYYY
Step-by-step explanation:
v= 4/3πr³
4/3×314/100×8×8×8
•
= 2,143.573
AB is tangent to circle D. Find the value of x.
Answer:
c 15
Step-by-step explanation:
Tangent AB is tangent to circle D at point A. The angle made by a tangent to a circle and a radius of the circle at the point of tangency is a right angle. That means that angle is a right angle, and triangle ABD is a right triangle.
We can use the Pythagoren theorem.
a^2 + b^2 = c^2
x^2 + 20^2 = (x + 10)^2
x^2 + 400 = (x + 10)(x + 10)
x^2 + 400 = x^2 + 10x + 10x + 100
400 = 20x + 100
20x = 300
x = 15
A box is filled with 9 red crayons, 2 blue crayons, and 5 yellow crayons. A crayon is chosen at random from the box. Find the probability that it is a red or a blue crayon. Write your answer as a fraction in simplest form.
Answer:
[tex]P(Red\ or\ Blue) = \frac{11}{16}[/tex]
Step-by-step explanation:
Given
[tex]Red = 9[/tex]
[tex]Blue = 2[/tex]
[tex]Yellow = 5[/tex]
Required
Probability of Red or Blue
First, it should be noted that the event described in the question are mutually exclusive or disjoint events;
Meaning that the probability of one have no effect the other;
Having said that; the Probability of Red ot Blue is as follows
[tex]P(Red\ or\ Blue) = P(Red) + P(Blue)[/tex]
Calculating [tex]P(Blue)[/tex]
[tex]P(Blue) = Number\ of\ blue\ crayon / total\ crayon[/tex]
[tex]P(Blue) = \frac{2}{9+ 2 + 5}[/tex]
[tex]P(Blue) = \frac{2}{16}[/tex]
Calculating [tex]P(Red)[/tex]
[tex]P(Red) = Number\ of\ red\ crayon / total\ crayon[/tex]
[tex]P(Red) = \frac{9}{9+ 2 + 5}[/tex]
[tex]P(Red) = \frac{9}{16}[/tex]
Substitute these values in the formula given above
[tex]P(Red\ or\ Blue) = P(Red) + P(Blue)[/tex]
[tex]P(Red\ or\ Blue) = \frac{9}{16} + \frac{2}{16}[/tex]
Take LCM
[tex]P(Red\ or\ Blue) = \frac{9 + 2}{16}[/tex]
[tex]P(Red\ or\ Blue) = \frac{11}{16}[/tex]
Hence, the probability of a red or blue crayon is
[tex]P(Red\ or\ Blue) = \frac{11}{16}[/tex]
A piece of string 8 inches long is cut into two pieces, one of which is of length x inches. If this piece is made into the circumference of a circle, and the other piece is made into the circumference of a square, then the combined area of the circle and square, as a function of x, is:
Answer:
2πr + 4a = 8
Step-by-step explanation:
HELP ME PLZ! I will not accept non sense answers. BRAINLIEST will be given to the person who gets it correct with full solutions.
[tex]A = 1500(1.00167)^{12t}[/tex]
=================================
Explanation:
You could use the formula
[tex]A = P(1+\frac{r}{n})^{nt}[/tex]
to plug in P = 1500, r = 0.02 and n = 12 to get the answer above. This is the compound interest formula. The interest rate r is divided into n = 12 to account for monthly compounding. The original exponent t turns into 12t. So for instance, if t = 2 years go by, then 12*t = 12*2 = 24 months have gone by.
For what values of x is x2 + 2x = 24 true?
–6 and –4
–4 and 6
4 and –6
6 and 4
Answer:
Option C
x²+ 2x -24=0
x²+6x-4x-24= 0
x(x+6) -4(x+6) = 0
(x+6)(x-4) = 0
x= -6 and 4
Therefore, for x = 4 and -6 , the above given equation is true.
For the following systems of equations, match each diagram on the left with its solution on the right.
Answer:
1. (2,1)
2. (6,-1)
3.(-2,3)
Answer:
1. (2,1)
2. (6,-1)
3. (-2,3)
Step-by-step explanation:
Each of the answer is consistent system because the lines intersect at one point, which is one solution.
Explain why 7 x 9 x 11 x 13 + 13 is a composite number.
Answer:
7 x 9 x 11 x 13 + 13 is a composite number because the answer is a positive number which is 9022.
7 x 9 x 11 x 13 + 13 is a positive integer that can be formed by multiplying small positive numbers which are 7, 9, 11 and 13. Equivalently, 9022 is a positive integer that has at least one divisor other than 1 and itself. For example, 9022 can be divided by 2. 9022 is exactly a number but it is not a prime number.
I hope you will understand my explanation!
52.85 rounded to the nearest tenth
Answer: 52.9
Step-by-step explanation:
The value 5 is rounded up.
Hope it helps <3
Answer:
52.9
Step-by-step explanation:
round up using the last number. since its 5, you round up
what is the exact area of a circle having diameter 4in
The length of the room is 2½ times the breadth. The perimeter of the room is 70 m. What are the length and breadth of the room.
Answer:
Length = 25 cmBreadth = 10 cmStep-by-step explanation:
Let breadth of the room be 'x'
Let length of the room be '[tex]2 \frac{1}{2} x = \frac{5}{2} = 2.5 \: x[/tex]'
Perimeter ( P ) = 70 cm
Now, let's find the breadth of the room 'x '
Perimeter of rectangle = [tex]2(l + b)[/tex]
plug the values
[tex]70 = 2(2.5x + x)[/tex]
Collect the like terms
[tex]70 = 2 \times 3.5x[/tex]
Calculate the product
[tex]70 = 7x[/tex]
Swap the sides of the equation
[tex]7x = 70[/tex]
Divide both sides of the equation by 7
[tex] \frac{7x}{7} = \frac{70}{7} [/tex]
Calculate
[tex]x = 10 \: cm[/tex]
Breadth = 10 cm
Now, Let's find the length of the room ' 2.5x '
Length of the room = [tex]2.5x[/tex]
Plug the value of X
[tex] = 2.5 \times 10[/tex]
Calculate the product
[tex] = 25 \: cm[/tex]
Thus , The length and breadth of the room is 25 cm and 10 cm respectively.
Hope this helps..
Best regards!!
WILL GIVE BRAILIEST! Find the mean of the data in the bar chart below. _________puppets
Answer: 2.5
Step-by-step explanation:
To find a mean, the average, we have to add everything together.
So we add 1 + 4 + 3 + 2, which is equal to 10. The next step to find the average is to divide by the total number of “things” which is the 4 puppeteers.
10/4 is 2.5
Help!!!!
Find the slope of the line on the graph.
Write your answer as a fraction or a whole
number, not a mixed number or decimal.
Enter the correct answer.
Answer:
[tex]Slope (m) = -\frac{2}{3}[/tex]
Step-by-step explanation:
To find the slope of the line of the graph, pick any 2 points on the line as your coordinate pairs.
Thus, on the line, let's pick 2 points as our coordinate pairs at:
When x = -6, y = 5 => (-6, 5), and
When x = 3, y = -1 => (3, -1)
Let (-6, 5) be (x1, y1), and (3, -1) be (x2, y2)
[tex] Slope (m) = \frac{y2 - y1}{x2 - x1} [/tex]
[tex] Slope (m) = \frac{-1 - 5}{3 - (-6)} [/tex]
[tex] Slope (m) = \frac{-1 - 5}{3 + 6} [/tex]
[tex] Slope (m) = \frac{-6}{9} [/tex]
[tex]Slope (m) = -\frac{2}{3}[/tex]
I NEED HELP QUICK like very quick
Answer:
2.5 or 2 1/2
Step-by-step explanation:
i caculated do order of operations
En un rectangulo el ancho es menor en 5cm al largo . si el P= 38cm calcule su area
Answer:
84cm²
Step-by-step explanation:
Perímetro de un rectángulo = 2L + 2W
Representemos la longitud del rectángulo = L
En la pregunta anterior se nos dijo que el ancho del rectángulo = es menor que 5 en la longitud
Por lo tanto, ancho del rectángulo = L - 5
Perímetro del rectángulo = 38 cm
Por lo tanto
38 = 2 (L) + 2 (L - 5)
38 = 2L + 2L - 10
38 + 10 = 4L
48 = 4L
L = 48/4
L = 12 cm
La longitud del rectángulo = 12 cm
Como L = 12, encontramos el ancho
Ancho = L - 5
= 12 cm - 5 cm
= 7 cm
El ancho del rectángulo = 7 cm
En la pregunta nos pidieron encontrar el área del rectángulo.
Área del rectángulo = Largo × Ancho
Área del rectángulo = 12 cm × 7 cm
Área del rectángulo = 84cm²
Lines m and n are parallel. Which of the other 5 named angles have a measure of 110°?
Which of these are true?
Answer:
<2, <5
Step-by-step explanation:
<2 is a vertical angle so it is equal to 110
<5 is a corresponding angle and since the lines are parallel it is also equal to 110
g(x)= √x+3 help plsss
Answer:
All real values of x such that x ≥-3
Step-by-step explanation:
g(x) = sqrt(x+3)
A sqrt must be greater than or equal to zero
sqrt (x+3) ≥ 0
Square each side
x+3≥ 0
Subtract 3 from each side
x ≥-3
The restrictions on x are x ≥-3
That means the domain is x ≥-3
All real values of x such that x ≥-3
Answer:
[tex]\boxed{\mathrm{B}}[/tex]
Step-by-step explanation:
[tex]g(x)=\sqrt{x+3}[/tex]
A square root must have a value of greater than or equal to 0.
[tex]\sqrt{x+3}\geq 0[/tex]
Square both sides.
[tex]x+3\geq 0[/tex]
Subtract 3 from both sides.
[tex]x\geq -3[/tex]
please i need help look at picture
Answer:
84
Step-by-step explanation:
Surface area is the combined area of the 2 dimensional planes.
6 × 5 + 3 × 4 × 1/2 × 2 + 6 × 3 + 4 × 6
30 + 12 + 18 + 24
= 84
The surface area is 84 square centimeters.
Solve for x. Write both solutions, separated by a
comma.
7x2 - 4x - 3=0
Answer:
x = - 3/7 or x = 1Step-by-step explanation:
7x² - 4x - 3 = 0
Rewrite - 4x as a difference
That's
7x² - 7x + 3x - 3 = 0
Factorize the expression
7x( x - 1) + 3 ( x - 1) = 0
(7x + 3)( x - 1 ) = 0
7x + 3 = 0 x - 1 = 0
7x = - 3 x = 1
x = -3/7
The solutions are
x = - 3/7 or x = 1
Hope this helps you
A cylinder shaped storage tank has a radius of (x+5) metres and a height of x metres. Determine the dimensions (round to two decimal places) of the tank if the volume is about 192 cubic metres.
Answer:
Radius = 6.46 meters
Height = 1.46 meters
Step-by-step explanation:
The volume of a cylinder = πr²h
In the above question, we were given
r = (x + 5) meters
h = x meters
Volume = 192 cubic meters
Hence,
192 = π × (x + 5)² × x
192 = π × (x² + 10x + 25) × x
192 = π × (x³ + 10x² + 25x)
Divide both sides by π
192/π = x³ + 10x² + 25x
61.115498147 = x³ + 10x² + 25x
x³ + 10x² + 25x - 61.12
This Quadratic equation is a polynomial
x = 1.46119
From the above:
Radius = (x + 5)meters
Radius = 1.46119 + 5 = 6.46119 meters
Approximately to 2 decimal places = 6.46 meters
Height = x meters
Height = 1.46119 meters
Approximately to 2 decimal places = 1.46 meters
The distance from Parrot Point Airport to the Ivy Cliffs is 178 miles at and angle of 7.1 degrees northeast. There is a wind blowing southeast at 30 miles per hour. You want to make this trip in 2 hours by flying straight there. At what speed* and heading should you fly? * Round the speed to the nearest tenth of a mile per hour and angle to the nearest tenth of a degree. Where north is 0 degrees and positive is clockwise.
Answer:
The speed is 74.0 miles per hour and the angle is 65.1° north-east
Step-by-step explanation:
We resolve the distance moved by the wind and plane into horizontal and vertical components. The direction moved horizontally by the plane is 178sin7.1 = 22 miles.
Since the wind is moving south east, it is at 45 south of east or a bearing of 135.
Since the wind speed is 30 mph and it takes 2 hours to complete the trip, the horizontal distance moved by the wind is vtcos135 = 30 × 2cos45 = 42.43 miles
Also, the vertical displacement moved by the wind is vtsin135 = -30 × 2 sin45 = -42.43 miles
The displacement moved vertically by the plane is 178cos7.1 = 176.64 miles
The total horizontal displacement of the plane is 22 miles + 42.43 miles = 62.43 miles
The total vertical displacement of the plane is 176.64 miles - 42.43 miles = 134.21 miles
The resultant displacement is thus d = √(62.43² + 134.21²) = 148.02 miles
The direction of this displacement is thus
Ф = tan⁻¹(total vertical displacement/total horizontal displacement)
= tan⁻¹(134.21/62.43)
= tan⁻¹(2.1498)
= 65.05°
= 65.1° to the nearest tenth degree.
The speed is thus v = distance/ time = 148.02 miles/ 2 hours = 74.01 mph ≅ 74 mph. Since the direction of the displacement is the direction of the velocity, the velocity is thus 74 miles per hour at 65.1° north-east.
So the speed is 74.0 miles per hour and the angle is 65.1° north-east
what is known as terms of ratio
Answer: The mathematics terms of ratio are the indicates many times one number contains to the another number.
Step-by-step explanation:Terms of ratio may be specified both constitution number or value to the equal correspond to the equal ratio.
"a to b"
"a:b"
There are Sixteen and eight apples and lemon in the table of fruit the ratio(that is 16:8 to the equivalent the ratio 8:4).
a:b=(a+b):a or ratio is equivalently a:b=(1+b/a):1.
The number in a terms ratio quantities of both numbers are to be positive
Help me pLEASSSSE ! do it step by step so I can see how y'all do it.
Answer:
5
Step-by-step explanation:
Since y equals 200 + 10x and y also equals 5x, then
200 + 10x = 50x
Subtract 10x from both sides.
200 = 40x
Divide both sides by 40.
5 = x
Answer: He must sell 5 sculptures.
A hair color manufacturer performed a survey which was normally distributed. They found that the average age at which a person's hair starts turning gray is 32 years, with a standard deviation of 4 years. Which of the following graphs displays the normal distribution of the average age at which a person's hair starts turning gray?
W.
X.
Y.
Z.
Answer: X
Step-by-step explanation: