Answer:
Reject the null hypothesis. There is sufficient evidence to conclude that the mean is less than 31%.
Step-by-step explanation:
In this case we need to test whether the popular charity has expenses that are higher than other similar charities.
The hypothesis for the test can be defined as follows:
H₀: The popular charity has expenses that are higher than other similar charities, i.e. μ > 0.31.
Hₐ: The popular charity has expenses that are less than other similar charities, i.e. μ < 0.31.
As the population standard deviation is not known we will use a t-test for single mean.
Compute the sample mean and standard deviation as follows:
[tex]\bar x=\frac{1}{n}\sum X=\frac{1}{10}\cdot[0.26+0.12+...+0.26]=0.238\\\\s= \sqrt{ \frac{ \sum{\left(x_i - \overline{X}\right)^2 }}{n-1} } = \sqrt{ \frac{ 0.0674 }{ 10 - 1} } =0.08654\approx 0.087[/tex]
Compute the test statistic value as follows:
[tex]t=\frac{\bar x-\mu}{s/\sqrt{n}}=\frac{0.238-0.31}{0.087/\sqrt{10}}=-2.62[/tex]
Thus, the test statistic value is -2.62.
Compute the p-value of the test as follows:
[tex]p-value=P(t_{\alpha, (n-1)}<-2.62}[/tex]
[tex]=P(t_{0.05,9}<-2.62)\\=0.014[/tex]
*Use a t-table.
Thus, the p-value of the test is 0.014.
Decision rule:
If the p-value of the test is less than the significance level then the null hypothesis will be rejected and vice-versa.
p-value = 0.014 < α = 0.05
The null hypothesis will be rejected at 5% level of significance.
Thus, concluding that there is sufficient evidence to conclude that the mean is less than 31%.
Total score: ____ of 20 points A marching band performs on the football field at half-time. As they perform, the members of the band stand in the shape of a sinusoidal function. While playing, they move, but still maintain the sinusoidal function, transforming it in different ways. Darla is a member of the marching band. As the band begins to play she is positioned in the exact center of the field. The person closest to her on the same horizontal line, stands 10 yards away. The sinusoidal function extends to the ends of the playing field. The playing area of football field measure 300 feet by 160 feet. Place the playing area of a football field on the coordinate plane such that the origin is the lower left corner of the football field. (Score for Question 1: ___ of 2 points) 1. What is the period and the amplitude of the sine function representing the position of the band members as they begin to play? Answer: (Score for Question 2: ___ of 6 points) 2. Edna is sitting in the stands and is facing Darla. Edna observes that sine curve begins by increasing at the far left of the field. What is the equation of the sine function representing the position of band members as they begin to play? Answer: (Score for Question 3: ___ of 4 points) 3. As the band begins to play, band members move away from the edges, and the curve reverses so that the function begins at the far left by decreasing. Darla does not move. The sine curve is now half as tall as it was originally. What is the equation of the sine curve representing the position of the band members after these changes? Answer: (Score for Question 4: ___ of 3 points) 4. Next, the entire band moves closer to the edge of the football field so that the sine curve is in the lower half of the football field from Edna’s vantage point. What is the equation of the sine curve representing the position of the band members after these changes? Answer: (Score for Question 5: ___ of 5 points) 5. At the end of the performance, the band marches off the field to the right, moving the entire sine curve. Asa grabs his camera to takes a picture of the entire football field. At the instant he takes the picture, the first person forming the curve now stands at the 5 yard line. What is the equation of the sine curve representing the position of the band members in Asa’s picture? Answer: Please help me explain step-by-step thank you
Answer:
1) Amplitude; A = 80 ft
Period = 60 ft
2)y = 80 sin ((π/30)x - 5π) + 80
3)y = 40 sin ((π/30)x - 5π) + 80
4)y = 40 sin ((π/30)x - 5π) + 40
5)y = -65sin ((π/30)x - 5π) + 80
Step-by-step explanation:
The general formula for sinusoidal wave equation is given by;
y = A sin (Bx - C) + D
Where;
A is amplitude = D_max or D_min
Period = 2π/B
So; B = 2π/Period
Phase Shift = C/B
So; C = B · Phase Shift
D: center
We are Given:
Height of the field is 160 ft and so the center is at y = 80. Thus; D = 80 ft
Thus; A = 80 ft
The person closest to Darla on the same horizontal line, stands 10 yards(30 ft) Thus, period = 2 × 30 = 60 ft
Thus; B = 2π/60 = π/30
Field is 300 ft wide and so the center is 300/2 = 150 ft
Thus; Phase Shift = 150.
C = B × Phase Shift = π/30 · 150 = 5π
1) From the calculations above,
Amplitude; A = 80 ft
Period = 60 ft
2) As they begin to play, from the calculations above and y = A sin (Bx - C) + D, equation of the sine function is now;
y = 80 sin ((π/30)x - 5π) + 80
3) In this, since the sine wave is half as tall, then after the changes, we have;
y = 40 sin ((π/30)x - 5π) + 80
4) since they have moved closer, then equation is now;
y = 40 sin ((π/30)x - 5π) + 40
5) We are Given:
Height of the field is 160 ft and so the center is at y = 80. Thus; D = 80 ft
Since the first person forming the curve now stands at the 5 yard line, the minimum is at 5 yds (15 ft). Thus;
D_min = 80 - 15 = 65. Thus; A = 65 ft
The person closest to Darla on the same horizontal line, stands 10 yards(30 ft) Thus, period = 2 × 30 = 60 ft
Thus; B = 2π/60 = π/30
Field is 300 ft wide and so the center is 300/2 = 150 ft
Thus; Phase Shift = 150.
C = B × Phase Shift = π/30 · 150 = 5π
The band ends down (at 15 feet) and thus A is negative
The equation is;
y = -65sin ((π/30)x - 5π) + 80
Part(1): The required values are,
Amplitude=[tex]80 ft[/tex] and Period: [tex]60 sec[/tex]
Part(2):
The equation of the sine function is
[tex]y=80 cos(\frac{\pi x}{30}+\pi)+80[/tex]
Part(3):
The equation of the sine curve is,
[tex]y=40cos(\frac{\pi x}{30})+80[/tex]
Part(4):
The equation of the sine curve representing the position of the band members after these changes is [tex]y=40cos(\frac{\pi x}{30})+40[/tex]
Part(5):
The required graph is attached below,
Simple harmonic motion:Simple Harmonic Motion or SHM is defined as a motion in which the restoring force is directly proportional to the displacement of the body from its mean position
Part(1):
Amplitude=[tex]\frac{1}{2} width=80ft[/tex]
Period=[tex]2\times 30=60 sec[/tex]
Part(2):
Let the equation be,
[tex]y=80 cos(\frac{\pi x}{30}+\pi)+80\\ y'=-\frac{8\pi}{3} sin((\frac{\pi x}{30}+\pi))[/tex]
Darla is at the point [tex]D(150,80)[/tex] which is on the graph at [tex]x=0[/tex] then,
[tex]80=80 cos(5\pi+\pi)=0\\y=-80 cos (\frac{\pi x}{30} )+80[/tex]
Part(3):
Since the wave is now [tex]\frac{160}{2} =80 ft[/tex] then,
Amplitude=40 ft
[tex]y=-4 cos (\frac{\pi x}{30} -\pi)+80\\y=40cos(\frac{\pi x}{30})+80[/tex]
Part(4):
The graph shifts downward 40 ft then,
[tex]y=-4 cos (\frac{\pi x}{30} -\pi)+80-40\\y=40cos(\frac{\pi x}{30})+40[/tex]
Part(5):
Start at:[tex]Y(x)=80sin (\frac{2\pi x}{60} )+80\\[/tex]
End at: [tex]Z(x)=80sin[ (\frac{2\pi }{60}(x-15) )]+80\\[/tex]
The graph is attached below:
Learn more about the topic of Simple harmonic motion:
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Paul Revere had to travel 3.5 miles to Boston from Charlestown by boat. From Charlestown to Lexington he was able to ride a horse that traveled at a rate of 1/8 mile per minute. His total distance traveled y is the sum of the distance to Charlestown and the distance from Charlestown to Lexington. Write a linear equation that could be used to find the distance y Paul Revere traveled in x minutes
Answer:
y = 3.5 + (1/8)x
Step-by-step explanation:
Speed is the ratio of total distance traveled to the total time taken. It is given by the formula:
Speed = distance / time.
The distance Paul Revere traveled from Charlestown to Boston is 3.5 miles.
Paul Revere also traveled from Boston to Lexington by horse at a rate of 1/8 mile per minute. If he traveled for x minutes, the distance covered can be gotten by:
Speed = distance / time
1/8 = distance / x
distance = (1/8)x miles.
y = sum of the distance to Charlestown and the distance from Charlestown to Lexington
y = 3.5 + (1/8)x
Determine the value of X. 30 POINTS
you can use the value of sin\
sin(theta) = 12/16
Now solve for theta, and do inverse sine
so theta would be 48.59037789 , or around 50 degrees
Answer:
48.59°Step-by-step explanation:
Since, it is a right triangle.
Perpendicular (p) = 12
hypotenuse ( h) = 16
now,
[tex]sin \: (x \: degree) = \frac{perpendicular}{hypotenuse} [/tex]
[tex]sin \: x \: = \frac{12}{16} [/tex]
[tex] x = {sin}^{ - 1} ( \frac{12}{16} )[/tex]
[tex]x = 48.59 \: degree[/tex]
hope this helps...
good luck on your assignment..
A 5.5-foot woman casts a shadow that is 3 feet longer than her son's shadow. The son casts a shadow 13.5 feet long.
Height of son =______
Woman
Height (ft)_______
Lenght of shadow (ft)_______
Son
Height (ft)_______
Lenght of shadow (ft)_______
Answer: 19!!
Step-by-step explanation:
Two points on line p have
coordinates (2, 1) and (5, 3).
The slope of the line is?
A. 2
B. 3/2
C. 1
D. 2/3
E. 4
Answer:
D. 2/3Step-by-step explanation:
[tex](2, 1) (5, 3)\\x_1 =2 \\y_1 =1\\x_2=5\\y_2 =3\\m =\frac{y_2-y_1}{x_2-x_1} \\\\m = \frac{3-1}{5-2} \\\\m = 2/3[/tex]
Translate to an equation and sole: The quotient of h and 26 is -52
he numbers of regular season wins for 10 football teams in a given season are given below. Determine the range, mean, variance, and standard deviation of the population data set. 2, 10, 15, 3, 13, 9, 14, 7, 2, 9 The range is nothing.
Answer:
Range = 13
Mean = 8.4
Variance= 21.24
Standard deviation= 4.61
Step-by-step explanation:
2, 10, 15, 3, 13, 9, 14, 7, 2, 9
For the range
Let the set of data be arranged inn ascending order
Range= higehest value- lowest value
Range = 15-2
Range= 13
For the mean
Mean = (2+2+3+7+9+9+10+13+14+15)/10
Mean = 84/10
Mean = 8.4
For variance
Variance=((2-8.4)²+(2-8.4)²+(3-8.4)²+(7-8.4)²+(9-8.4)²+(9-8.4)²+(10-8.4)²+(13-8.4)²+(14-8.4)²+(15-8.4)²)/10
Variance= (40.96+40.96+29.16+1.96+0.36+0.36+2.56+21.16+31.36+43.56)/10
Variance= 212.4/10
Variance= 21.24
Standard deviation= √variance
Standard deviation= √21.24
Standard deviation= 4.609
Approximately = 4.61
Tamara was asked to write an example of a linear functional relationship. She wrote this example: My babysitting service charges an initial $5.00 fee plus an additional $6.50 per hour. Complete the table below to show the babysitting rate for different numbers of total hours. Then write a linear equation in the form y=mx+b that represents this relationship where m is the slope and b is the y-intercept. Use the on-screen keyboard to type your answers in the boxes below. Total Hours 1 $
2 $
3 $
4 $
Answer:
Hours Charge
1 y = 6.5(1) + 5 = $11.5
2 y = 6.5(2) + 5 = $18
3 y = 6.5(3) + 5 = $24.5
4 y = 6.5(4) + 5 = $31
Step-by-step explanation:
In an equation y=mx+b, we can interpret the intercept b as the value of the initial charge and the slope m as the additional charge per hour. So, we can formulate the following equation:
y = 6.5x + 5
Where x is the hours and y are the charges for the babysitting, so, we can fill the table as:
Hours Charge
1 y = 6.5(1) + 5 = $11.5
2 y = 6.5(2) + 5 = $18
3 y = 6.5(3) + 5 = $24.5
4 y = 6.5(4) + 5 = $31
The answer should be like
Hours Charge
1 y = 6.5(1) + 5 = $11.5
2 y = 6.5(2) + 5 = $18
3 y = 6.5(3) + 5 = $24.5
4 y = 6.5(4) + 5 = $31
Calculation of the number of hours:Since we know that the equation should be in the form of
y = mx + b
So, here
y = 6.5x + 5
Here x is the hours and y are the charges for the babysitting.
So, the table be like
Hours Charge
1 y = 6.5(1) + 5 = $11.5
2 y = 6.5(2) + 5 = $18
3 y = 6.5(3) + 5 = $24.5
4 y = 6.5(4) + 5 = $31
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A couch sells for $820. Instead of paying the total amount at the time of purchase, the same couch can be bought by paying $400 down and $60 per month for 12 months. How much is saved by paying the total amount at the time of purchase?
Answer:
$300
Step-by-step explanation:
The couch is sold in two ways; outright payment or installment payment.
Outright payment would cost = $820
Installment payment = down payment + monthly charges
Down payment = $400
Monthly charges for a period of one year (12 months) = 12 × $60
= $720
Installment payment would cost = $400 + $720
= $1120
Amount saved by paying total amount at the time of purchase = $1120 - $820
= $300
Thus, the outright buying the couch would save $300.
Of 10 girls in a class, three have blue eyes. Two of the girls are chosen at random. Find the probability that: (a) both have blue eyes; (c) at least one has blue eyes; (b) neither has blue eyes; (d) exactly one has blue eyes.
Answer:
C.
Step-by-step explanation:
It's the most reasonable answer.
The floor of a room is 8m 96cm long and 6m 72cm broad. Find the maximum dimension of a square tile
of the same size needed to cover the entire floor.
A sector with a central angle measure of 200 degrees has a radius of 9 cm. What is the area of the sector?
Answer:
[tex]\boxed{Area\ of\ sector = 141.4\ cm^2}[/tex]
Step-by-step explanation:
Radius = r = 9 cm
Angle = θ = 200° = 3.5 radians
Now,
[tex]Area \ of \ sector = \frac{1}{2} r^2 \theta[/tex]
Area = 1/2 (9)²(3.5)
Area = 1/2 (81)(3.5)
Area = 282.7 / 2
Area of sector = 141.4 cm²
Answer:
45 pi cm^2 or 141.3 cm^2
Step-by-step explanation:
First find the area of the circle
A = pi r^2
A = pi (9)^2
A = 81 pi
A circle has 360 degrees
The shaded part has 200
The fraction that is shaded is
200/360 =5/9
Multiply by the total area
5/9 * 81 pi
45 pi
Using 3.14 for pi
141.3
45 pi cm^2 or 141.3 cm^2
[PLEASE HELP] in the function above, the slope of it will be multiplied by -4, and it’s y value of the y intercept will be decreased by only 1 units, which of these following graphs best represent the new function???
Answer:
Z (The one on the bottom right)
Step-by-step explanation:
You said that the y intercept goes down by 1 unit which makes only W and Z possible.
The slope is 1/2 and if you multiply that by -4 the new slope is -2 which means the change in y is -2 every time the change in x is 1. Which perfectly fits Z and if you have any questions please ask me with the comments!
The minimum point on the graph of the equation y = f(x) is (-1, -3). What is the minimum point
on the graph of the equation y = f(x – 5)?
Answer:
(4, -3)
Step-by-step explanation:
the equation f(x-5) is a translation of the equation f(x) by 5 units to the right.
So, if all points of the equation f(x) are shifted 5 units to the right, the minimum point of the graph is also shifted 5 units to the right, so to find the minimum point of y = f(x - 5), we just need to sum 5 units to the x-coordinate:
Minimum point = (-1 + 5, -3) = (4, -3)
So the minimum point of y = f(x - 5) is (4, -3).
The minimum point on the graph of y = f(x - 5) is (-6,3)
On the graph of the equation y = f(x);
The minimum point is given as (-1,-3)
The graph of y = f(x - 5) means that, f(x) is shifted to the right by 5 units
So, the corresponding point of (x,y) of f(x) on the graph of f(x - 5) is:
[tex](x,y) \to (x - 5,y)[/tex]
This gives
[tex](-1,-3) \to (-1 - 5,3)[/tex]
Subtract 5 from -1
[tex](-1,-3) \to (-6,3)[/tex]
Hence, the minimum point on the graph of y = f(x - 5) is (-6,3)
Read more about translation at:
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6th grade math help me, please. :)
Answer: 120 ice creams total
The answer is option D
A triangle has side lengths of 13, 9, and 5. Is the triangle a right triangle? Explain.
Use complete sentences in your explanation.
Hint: Pythagorean Theorem: a^2+ b^2 = c^2
Answer:
see below
Step-by-step explanation:
Using the Pythagorean Theorem:
a^2+ b^2 = c^2
5^2+ 9^2 = 13^2
25+81 = 169
106 = 169
This is not true so it is not a right triangle
Answer:
[tex]\boxed{\sf Not \ a \ right \ triangle}[/tex]
Step-by-step explanation:
Apply Pythagorean theorem to check if the triangle is a right triangle.
[tex]a^2+ b^2 = c^2[/tex]
[tex]5^2+ 9^2 = 13^2[/tex]
[tex]25+81=169[/tex]
[tex]106=109[/tex]
False statement.
The triangle is not a right triangle.
Which choice is equivalent to 4 square root 8
Answer:
A
Step-by-step explanation:
............................ ....
I will give brainliest
Answer: 10.246950766
Step-by-step explanation:
based on Pythagorean’s theorem:
[tex]\sqrt{19^{2}-16^{2} } =\sqrt{105} = 10.246950766[/tex]
find the slope (7,1)(5,0)
Answer:
1/2x
Step-by-step explanation:
To find the slope of a line with only 2 points we use the following formula.
[tex]\frac{y^2-y^1}{x^2-x^1}[/tex],
So we fill it in with the following points,
(7,1)
(5,0)
0 is y2 and 1 is y1 0-1 = -1
5-7 = -2
Slope: 1/2
Thus,
the slope of the line is 1/2.
Hope this helps :)
A family paid $28,500 as a down payment for a home. If this represents 15% of the price of the home, what is the price of the home.
Answer:
.15* house price = 28,500
house price = 28,500 / .15
house price = 190,000
Step-by-step explanation:
Answer: 190,000
Step-by-step explanation:
the equation looks like this - .15x=28,500. then you divide both sides by .15 and get x=190,000
What the answer now fast
Answer:
[tex]m < C = 60[/tex]
Step-by-step explanation:
From the given right angled triangle, ∆ABC,
[tex] BC = Hypotenuse = 2\sqrt{11} [/tex]
[tex] AC = Adjacent = \sqrt{11} [/tex]
Thus, m<C can be found by applying the following trigonometric ratio formula as shown below:
[tex] cos(C) = \frac{adjacent}{hypotenuse} [/tex]
[tex] cos(C) = \frac{\sqrt{11}}{2\sqrt{11}} [/tex]
Evaluate: √11 cancels √11
[tex] cos(C) = \frac{1}{2} [/tex]
[tex] cos(C) = 0.5 [/tex]
[tex] C = cos^{-1}(0.5) [/tex]
[tex] C = 60 [/tex]
[tex]m < C = 60[/tex]
The slope intercept form of a line is
y=mx+b
The slope is represented by____
The y-intercept is represented by____
Answer:y=Mx+b
Step-by-step explanation:
Question 3 (5 points)
POINT
-POINT A
POINT B
What are the coordinates of the point labeled B in the graph shown above?
A) (3, 2)
B) (-3,2)
OC) (-2,3)
D) (-2, -3)
Question 4 (5 points)
Answer:
(D) -2,-3
Step-by-step explanation:
From the origin, we can find the current position of point B by counting.
B is 2 to the left of the y-axis, meaning that it's x value is -2.
B is 3 down of the x-axis, making it's y value -3.
Therefore, the coordinates of point B are -2,-3.
Hope this helped!
Answer: (D) -2,-3
Step-by-step explanation:
What is the range of the function f(x)=3/4|x|-3
Range is [tex]y\in[-3,+\infty)[/tex].
Hope this helps.
Consider a binomial experiment with 15 trials and probability 0.35 of success on a single trial.
(a) Use the binomial distribution to find the probability of exactly 10 successes (Round your answer to three decimal places.)
(b) Use the normal distribution to approximate the probability of exactly 10 successes. (Round your answer to three decimal places.) (
(c) Compare the results of parts (a) and (b).
A. These results are fairly different.
B. These results are almost exactly the same.
Answer:
a
[tex]P(X = 10 ) = 0.0096[/tex]
b
[tex]P(X = 10 ) = 0.0085[/tex]
c
Option A is correct
Step-by-step explanation:
From the question we are told that
The sample size is n = 15
The probability of success is [tex]p = 0.35[/tex]
The number of success we are considering is r = 10
Now the probability of failure is mathematically evaluated as
[tex]q = 1- p[/tex]
substituting value
[tex]q = 1- 0.35[/tex]
[tex]q = 0.65[/tex]
Now using the binomial distribution to find the probability of exactly 10 successes we have that
[tex]P(X = r ) = [\left n } \atop {r}} \right. ] * p^r * q^{n- r}[/tex]
substituting values
[tex]P(X = 10 ) = [\left 15 } \atop {10}} \right. ] * p^{10}* q^{15- 10}[/tex]
Where [tex][\left 15 } \atop {10}} \right. ][/tex] mean 15 combination 10 which is evaluated with a calculator to obtain
[tex][\left 15 } \atop {10}} \right. ] = 3003[/tex]
So
[tex]P(X = 10 ) = 3003 * 0.35 ^{10}* 0.65^{15- 10}[/tex]
[tex]P(X = 10 ) = 0.0096[/tex]
Now using the normal distribution to approximate the probability of exactly 10 successes, we have that
[tex]P(X = r ) = P( r < X < r )[/tex]
Applying continuity correction
[tex]P(X = r ) = P( r -0.5 < X < r +0.5)[/tex]
substituting values
[tex]P(X = 10) = P( 10-0.5 < X < 10+0.5)[/tex]
[tex]P(X = 10 ) = P( 9.5 < X < 10.5)[/tex]
Standardizing
[tex]P(X = r ) = P( \frac{9.5 - \mu }{\sigma } < \frac{X - \mu }{\sigma } < \frac{10.5 - \mu}{\sigma } )[/tex]
The where [tex]\mu[/tex] is the mean which is mathematically represented as
[tex]\mu = n * p[/tex]
substituting values
[tex]\mu = 15 * 0.35[/tex]
[tex]\mu = 5.25[/tex]
The standard deviation is evaluated as
[tex]\sigma = \sqrt{n * p * q }[/tex]
substituting values
[tex]\sigma = \sqrt{15 * 0.35 * 0.65 }[/tex]
[tex]\sigma = 1.8473[/tex]
Thus
[tex]P(X = 10 ) = P( \frac{9.5 - 5.25 }{1.8473 } < \frac{X - 5.25 }{1.8473 } < \frac{10.5 - 5.25}{1.8473 } )[/tex]
[tex]P(X = 10 ) = P( 2.30 < Z < 2.842 )[/tex]
[tex]P(X = 10 ) = P(Z < 2.842 ) - P(Z < 2.30 )[/tex]
From the normal distribution table we obtain the [tex]P(Z < 2.841)[/tex] as
[tex]P(Z < 2.841) = 0.99775[/tex]
And the [tex]P(Z < 2.30)[/tex]
[tex]P(Z < 2.30) = 0.98928[/tex]
There value can also be obtained from a probability of z calculator at (Calculator dot net website)
So
[tex]P(X = 10) = 0.99775 - 0.98928[/tex]
[tex]P(X = 10 ) = 0.0085[/tex]
Looking at the calculated values for question a and b we see that the values are fairly different.
Whats the input value of f(x)=2x+5
Answer:
x
Step-by-step explanation:
f(x)=2x+5
Input: x
Output: f(x)
For i.e:
Input: 1
Output: f(1) = 2(1) + 5 = 2 + 5 = 7
Find the value of x.
Explanation:
For any quadrilateral that is inscribed in a circle, ie has all four points on the circle like this, the opposite angles are always supplementary. They add to 180 degrees.
x+125 = 180
x+125-125 = 180-125 ... subtract 125 from both sides
x = 55
A chemical company makes two brands of antifreeze. The first brand is 45% pure antifreeze, and the second brand is 95% pure antifreeze. In order to obtain 70 gallons of a mixture that contains 65% pure antifreeze, how many gallons of each brand of antifreeze must be used?
Answer:
42 gallons 45% antifreeze
28 gallons 95% antifreeze
Step-by-step explanation:
If x is volume of 45% antifreeze, and y is volume of 95% antifreeze, then the total volume is:
x + y = 70
And the total amount of antifreeze is:
0.45 x + 0.95 y = 0.65 (70)
Solving by substitution:
0.45 x + 0.95 (70 − x) = 0.65 (70)
0.45 x + 66.5 − 0.95 x = 45.5
21 = 0.5 x
x = 42
y = 28
Before hosting their annual Chess Tournament and Spelling Bee, a school received 7 boxes of honorary medals: one medal for every participant. After the Chess Tournament, two boxes were empty and the rest were still closed. After the Spelling Bee, which had twice as many participants, there were 72 medals left. How many people competed in the Chess Tournament?
Answer:
144 people competed in the Chess Tournament
Step-by-step explanation:
So as you can see, after the Chess Tournament took place, two boxes were empty, the rest closed. That would mean that there were 2 boxes of medals that were given out to honor the participants in the chess tournament. The spelling bee had twice as many participants, and hence used 2 [tex]*[/tex] 2 = 4 boxes. The remaining box had to have 72 medals in it, as it was the remaining amount of medals.
After the Chess Tournament, 2 boxes were given out, and we can assume they contained 72 medals in them. Therefore, the number of medals given after the chess tournament would be 2 [tex]*[/tex] 71 = 144 medals. Each medal corresponds to a participant, so the number of chess tournament participants would also be 144, 144 participants.
Find the equation for the plane through the point Upper P 0equals(2 comma 5 comma 9 )and normal to the vector nequals5 Bold i plus 8 Bold j plus 2 Bold k.
Answer:
5x+8y+2z = 68
Step-by-step explanation:
Given the point P0 = (2, 5, 9), to Find an equation for a plane through that point and normal to the vector n = 5i+8j+2k the following steps must be followed:
The equation for the plane passing through the point is expressed as;
a(x-x0)+b(y-y0)+c(z-z0) = 0 where;
(x0, y0, z0) is the point on the plane and (a,b,c) is the normal vector n.
Given the point (2, 5, 9) and normal vector n =(5, 8, 2)
x0 = 2, y0 = 5, z0 = 9, a = 5, b = 8 and c= 2.
Substituting this values into the equation of the plane above will give;
5(x-2)+8(y-5)+2(z-9) = 0
On expansion:
5x-10+8y-40+2z-18 = 0
5x+8y+2z-10-40-18 = 0
5x+8y+2z-68 = 0
The required equation of the plane is 5x+8y+2z = 68