Answer:
D. 750(0.75)ˣ
Step-by-step explanation:
Let the new brightness be L'. Since our initial brightness L₀ reduces by 25 %, we have that L' = L₀ - 25% of L₀
L' = L₀ - 0.25L₀
L' = 0.75L₀
Adding the second screen, the new intensity is L" = L' - 25 % of L'
L" = L' - 0.25 L'
L" = 0.75L'.
Since L' = 0.75L₀,
L" = 0.75L' = 0.75(0.75L₀) = 0.75²L₀
Adding the third screen, the new intensity is L"' = L'' - 25 % of L''
L'" = L" - 0.25 L"
L"' = 0.75L".
Since L" = 0.75L' = 0.75²L₀
L"' = 0.75L" = 0.75(0.75²L₀) = 0.75³L₀
So, we see a pattern here.
The intensity after x screens is L = (0.75)ˣL₀
Since L₀ = 750 lumens,
L = 750(0.75)ˣ
a car travels 10 km southeast and 15 km in a direction 60 degrees north of east. find the magnitude and direction
Answer:
the car travels 10km then 15km 60* north of east
Step-by-step explanation:
Respond to each of the four questions.
Describe the steps to graphing a linear equation. Be sure to provide an example to illustrate your description.
Describe the steps to graphing a quadratic equation. Be sure to provide an example to illustrate your description.
Describe how to solve a linear equation. Be sure to provide an example to illustrate your description.
Describe how to solve a quadratic equation. Be sure to provide an example to illustrate your description.
Answer:hello
Step-by-step explanation:
1+1
I need help solving this problem .
Step-by-step explanation:
here is the answer to your question
J. Aitchison collected expenditures data for 20 randomly selected single men and 20 randomly selected single women. He uses the data to conduct a hypothesis test to determine if the mean percent of expenditures that goes toward housing (including fuel and light) is different for men and women. What is the correct alternative hypothesis?
a. Md = 0
b. μα = 0
c. ud > 0
d. Opmen — Вwomen
e. Himen > Mwomen
f. Mmen Mwomen
Answer:
The alternative hypothesis is [tex]H_1: \mu_M - \mu_W \neq 0[/tex], considering M for men and W for women.
Step-by-step explanation:
He uses the data to conduct a hypothesis test to determine if the mean percent of expenditures that goes toward housing (including fuel and light) is different for men and women.
At the null hypothesis, we test if there is not difference, that is, the difference of the mean is 0, so:
[tex]H_0: \mu_M - \mu_W = 0[/tex]
At the alternative hypothesis, we test if there is a difference, that is, the difference of the means is different of 0, so:
[tex]H_1: \mu_M - \mu_W \neq 0[/tex]
Solve the equation
tan^2 thetha-3 tan thetha+2=0 for 0
Step-by-step explanation:
[tex]\tan^2 \theta - 3\tan \theta + 2 = 0[/tex]
Let [tex]x = \tan \theta[/tex]
We can then write
[tex]x^2 -3x + 2 = 0\:\:\Rightarrow\:\:(x - 2)(x - 1) = 0[/tex]
or
[tex](\tan \theta - 2)(\tan \theta - 1) = 0[/tex]
The zeros occur when
[tex]\tan \theta = 2\:\:\:\text{or}\:\:\:\tan \theta = 1[/tex]
or when [tex]\theta = 63.4°[/tex] or [tex]\theta = 45°[/tex].
Javier volunteers in community events each month. He does not do more than five events in a month. He attends exactly five events 25% of the time, four events 30% of the time, three events 20% of the time, two events 15% of the time, one event 5% of the time, and no events 5% of the time. Find the probability that Javier volunteers for less than three events each month. P (x < 3) = 2 Find the expected number of events Javier volunteers in a month. 3.6 It is given that x must be below a certain value, which limits the rows to use in the PDF table. What is the sum of the probabilities of those rows?
Answer:
[tex]P(x < 3) = 25\%[/tex]
[tex]E(x) = 3[/tex]
Step-by-step explanation:
The given parameters can be represented as:
[tex]\begin{array}{ccccccc}x & {5} & {4} & {3} & {2} & {1}& {0} & P(x) & {25\%} & {30\%} & {20\%} & {15\%} & {5\%} & {5\%} \ \end{array}[/tex]
Solving (a): P(x < 3)
This is calculated as:
[tex]P(x < 3) = P(x = 0) + P(x = 1) + P(x =2)[/tex] ----- i.e. all probabilities less than 3
So, we have:
[tex]P(x < 3) = 5\% + 5\% + 15\%[/tex]
[tex]P(x < 3) = 25\%[/tex]
Solving (b): Expected number of events
This is calculated as:
[tex]E(x) = \sum x * P(x)[/tex]
So, we have:
[tex]E(x) = 5 * 25\% + 4 * 30\% + 3 * 20\% + 2 * 15\% + 1 * 5\% + 0 * 5\%[/tex]
[tex]E(x) = 125\% + 120\% + 60\% + 30\% + 5\% + 0\%[/tex]
[tex]E(x) = 340\%[/tex]
Express as decimal
[tex]E(x) = 3.40[/tex]
Approximate to the nearest integer
[tex]E(x) = 3[/tex]
19. Divide 6/13 by 6/12.
A. 12/13
B. 13/12
c. 1/12
D.9/16
Answer:
12/13 is the answer
Step-by-step explanation:
A town recently dismissed 5 employees in order to meet their new budget reductions. The town had 4 employees over 50 years of age and 16 under 50. If the dismissed employees were selected at random, what is the probability that no more than 1 employee was over 50
Answer:
0.7513 = 75.13% probability that no more than 1 employee was over 50
Step-by-step explanation:
The employees are chosen from the sample without replacement, which means that the hypergeometric distribution is used to solve this question.
Hypergeometric distribution:
The probability of x successes is given by the following formula:
[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}[/tex]
In which:
x is the number of successes.
N is the size of the population.
n is the size of the sample.
k is the total number of desired outcomes.
Combinations formula:
[tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
In this question:
4 + 16 = 20 employees, which means that [tex]N = 20[/tex]
4 over 50, which means that [tex]k = 4[/tex]
5 were dismissed, which means that [tex]n = 5[/tex]
What is the probability that no more than 1 employee was over 50?
Probability of at most one over 50, which is:
[tex]P(X \leq 1) = P(X = 0) + P(X = 1)[/tex]
In which
[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}[/tex]
[tex]P(X = 0) = h(0,20,5,4) = \frac{C_{4,0}*C_{16,5}}{C_{20,5}} = 0.2817[/tex]
[tex]P(X = 1) = h(1,20,5,4) = \frac{C_{4,1}*C_{16,4}}{C_{20,5}} = 0.4696[/tex]
Then
[tex]P(X \leq 1) = P(X = 0) + P(X = 1) = 0.2817 + 0.4696 = 0.7513[/tex]
0.7513 = 75.13% probability that no more than 1 employee was over 50
Jill has 32 crayons. She loses 4 of the crayons. How many are left?
Answer:
the answer here is d
the answer is d
Answer:
28
Step-by-step explanation:
Total number of crayons = 32
Number of crayons lost = 4
Therefore, number of crayons she is left with is : 32 - 4 = 28
Working :
[tex]32\\04 - \\\overline{28}[/tex]
the voltage in a lightbulb is given by the equation V= IR. in this equation V is the voltage, I is the current , and R is the resistance. what is the current in a lightbulb with a voltage of 35.0 V and a resistance of 175
Answer:
a
Step-by-step explanation:
Find the direction cosines and direction angles of the vector. (Give the direction angles correct to the nearest degree.) c, c, c , where c > 0
Answer:
cos(∝) = 1/√3
cos(β) = 1/√3
cos(γ) = 1/√3
∝ = 55°
β = 55°
γ = 55°
Step-by-step explanation:
Given the data in the question;
vector is z = < c,c,c >
the direction cosines and direction angles of the vector = ?
Cosines are the angle made with the respect to the axes.
cos(∝) = z < 1,0,0 > / |z|
so
cos(∝) = < c,c,c > < 1,0,0 > / √[c² + c² + c²] = ( c + 0 + 0 ) / √[ 3c² ]
cos(∝) = c / √[ 3c² ] = c / c√3 = 1/√3
∝ = cos⁻¹( 1/√3 ) = 54.7356° ≈ 55°
cos(β) = < c,c,c > < 0,1,0 > / √[c² + c² + c²] = ( 0 + c + 0 ) / √[ 3c² ]
cos(β) = c / √[ 3c² ] = c / c√3 = 1/√3
β = cos⁻¹( 1/√3 ) = 54.7356° ≈ 55°
cos(γ) = < c,c,c > < 0,0,1 > / √[c² + c² + c²] = ( 0 + 0 + c ) / √[ 3c² ]
cos(γ) = c / √[ 3c² ] = c / c√3 = 1/√3
γ = cos⁻¹( 1/√3 ) = 54.7356° ≈ 55°
Therefore;
cos(∝) = 1/√3
cos(β) = 1/√3
cos(γ) = 1/√3
∝ = 55°
β = 55°
γ = 55°
A chemical engineer must report the average volume of a certain pollutant produced by the plants under her supervision. Here are the data she has been given by each plant:plantvolume of pollutantPittCross CreekSusquehannaWhat average volume should the chemical engineer report
Answer:
Please find the complete question in the attached file.
Step-by-step explanation:
Total quantities of plant-produced pollutants:
[tex]=(10.88+15.82+0.92) \ L\\\\=27.62\ L[/tex]
We are three medicinal plants here, Pinecrest, Macon, and Ogala. The average number of contaminants produced by plants would be
[tex]\to 27.62\div 3 \\\\\to \frac{27.62}{3} \\\\ \to 9.206 \ L[/tex]
TZ is a midsegment, which of the following statements CANNOT be true
Answer:
Option C: QT < TR
Step-by-step explanation:
From the triangle, we can see that UX bisects RS into two equal parts and so it is a perpendicular bisector.
TZ Is a mid segment and it means that T bisects QR into 2 equal parts as well as QS into 2 equal parts.
Thus;
QT = QR
And QZ = SZ
So Option C is not correct because QT = QR
In the diagram, WZ=StartRoot 26 EndRoot.
On a coordinate plane, parallelogram W X Y Z is shown. Point W is at (negative 2, 4), point X is at (2, 4), point Y is at (1, negative 1), and point Z is at (negative 3, negative 1).
What is the perimeter of parallelogram WXYZ?
units
units
units
units
Answer:
[tex]P = 8 + 2\sqrt{26}[/tex]
Step-by-step explanation:
Given
[tex]W = (-2, 4)[/tex]
[tex]X = (2, 4)[/tex]
[tex]Y = (1, -1)[/tex]
[tex]Z = (-3,-1)[/tex]
Required
The perimeter
First, calculate the distance between each point using:
[tex]d = \sqrt{(x_1 - x_2)^2 + (y_1 -y_2)^2[/tex]
So, we have:
[tex]WX = \sqrt{(-2- 2)^2 + (4-4)^2 } =4[/tex]
[tex]XY = \sqrt{(2- 1)^2 + (4--1)^2 } =\sqrt{26}[/tex]
[tex]YZ = \sqrt{(1- -3)^2 + (-1--1)^2 } =4[/tex]
[tex]ZW = \sqrt{(-3--2)^2 + (-1-4)^2 } =\sqrt{26}[/tex]
So, the perimeter (P) is:
[tex]P = 4 + \sqrt{26} + 4 + \sqrt{26}[/tex]
[tex]P = 8 + 2\sqrt{26}[/tex]
Answer:
its D.
Step-by-step explanation:
took test
Cole biked at 5 mph for 1 hours. Which of the following choices show how far he biked?
A=5.5 miles
B=6.5 miles
C=7.5 miles
D=10 miles
Answer:
Most Likely A, 5.5 Miles
Step-by-step explanation:
However the question doesn't make sense as the logical answer is simply 5 miles, but the safest choice is 5.5
In a right triangle, the lengths of the two legs are 8 cm and 10 cm respectively. Find the hypotenuse of the triangle.
9 cm
10.5 cm
12 cm
12.8 cm
12.8, pythagorean theorem.
William has been contracted to paint a school classroom. The classroom is 20 m long, 15 m wide and 5 m high. There are four windows (2m by 3m) and a door (2m by 1m). Determine the cost of painting the ceiling at N$ 6.50/m²
Answer:
Step-by-step explanation:
l -> length
b -> width
h -> height
Find the area of four walls and ceiling. then subtract the area of four windows and a door form that area.
Area of four walls + ceiling = 2( lh + bh) +lb
= 2*(20*5 + 15*5) + 20*15
= 2( 100 + 75) + 300
= 2* 175 + 300
= 350 +300
= 650 sq m
Area of window = 2 *3 = 6 sq.m
Area of four windows = 4*6 = 24 sq.m
Area of door = 2 * 1 = 2 sq.m
Area of four walls excluding 4 windows and door = 650 - 24 - 2 = 624 sq.m
Cost of painting = 624 * 6.50
= $ 4056
Answer: 1950 dollars to paint the ceiling only (ignoring the walls)
The cost to paint the walls only is 2106 dollars.
The cost to paint the walls and ceiling is 4056 dollars.
==================================================
Explanation:
It seems a bit strange how your teacher mentions the windows and doors, but then asks about the ceiling only. Perhaps this is a red herring, but I'm not sure.
Anyway, to directly answer the question, we'll need to find the area of the ceiling first. The ceiling is a rectangle of dimensions 20 m by 15 m, so its area is 20*15 = 300 square meters.
Since paint costs 6.50 dollars per square meter, the total cost for the ceiling alone is 6.50*300 = 1950 dollars
If your teacher only cares about the ceiling, then you can stop here (and ignore the next section below).
---------------------------
If you wanted to find the cost to paint the walls, then we need to find the area of the walls.
For now, ignore the windows and door. Two opposite walls have area of 20*5 = 100 m^2 each. That accounts for 2*100 = 200 m^2 of wall area so far.
The other pair of opposite walls have area 15*5 = 75 m^2 each. That's another 2*75 = 150 m^2 of wall area.
In all, the total wall area without considering the windows or door is 200+150 = 350 m^2.
Now we consider the windows. Each window is 2 m by 3 m, yielding an area of 2*3 = 6 m^2. Four such windows have a total area of 4*6 = 24 m^2.
The door is 2 m by 1 m, so its area is 2*1 = 2 m^2
We'll subtract the wall area and the combined window+door areas to get
wallArea - windowArea - doorArea = 350-24-2 = 324
So after accounting for the windows and door, the amount of wall to paint is 324 m^2, which leads to a cost of 6.50*324 = 2106 dollars.
Therefore, painting the walls and ceiling gets us a total cost of 1950+2106 = 4056 dollars
This section is entirely optional if your teacher only cares about the ceiling.
If 6 playes cost 54$ how much do 30 plates cost
Answer:
270 plates
Step-by-step explanation:
First, you need to find how much one plate costs.
6x = 54
---- ----
6 6
x = 9
Now, multiply 30 plates with x, which is 9.
30(9) = 270
The answer is 270.
Answer:
270
Step-by-step explanation:
54($)÷6= 9 then 9×30=270
The ocean surface is at 0 ft elevation. A diver is underwater at a depth of 138 ft. In this area, the ocean floor has a depth of 247 ft. A rock formation rises to a peak 171 ft above the ocean floor. How many feet below the top of the rock formation is the diver?
Answer:
The ocean surface is at 0 ft elevation. A diver is underwater at a depth of 138 ft. In this area, the ocean floor has a depth of 247 ft.
Step-by-step explanation:
Can someone please help me with this math problem.
Answer:
8 + 30 ÷ 2 + 4 = 27
8 + 30 ÷ (2 + 4 ) = 13
(8 + 30) ÷ 2 + 4 = 23
Step-by-step explanation:
A senior class of 420 students will rent buses and vans for a class trip. Each bus can transport 50 students and 3 chaperones and costs $1200 to rent. Each van can transport 10 students and 1 chaperone and costs $100 to rent. There are 36 chaperones available (so they can't all go in vans). How many vehicles of each type should be rented in order to minimize the cost
Answer:
37 buses and 1 van.
Step-by-step explanation:
The cost to rent a van is $1200 for 50 students and 3 chaperones, while a bus for 10 students and a chaperone is $100 .
The cost of renting buses for 50 students is $500
What we do is rent 37 buses and 1 van
37 buses will take in 370 students with empty 2 spaces in 2 buses for chaperones since the chaperones are 36.
Then rent 1 van to take in 50 students and 1 chaperone.
The total cost here will be
$3700 + $1200 = $ 4900
This will help to safe cost.
Exactly how many planes contain points J, K, and N?
a - 0
b - 1
c - 2
d - 3
what is the range of the funcion y=x^2
Answer:
Range = [0, infinity)
Step-by-step explanation:
Minimum point of the graph is at (0,0) and it is a u shaped graph. Hence, range is 0 inclusive to infinity
The following data was collected to explore how the average number of hours a student studies per night and the student's GPA affect their ACT score. The dependent variable is the ACT score, the first independent variable (x1)is the number of hours spent studying, and the second independent variable (x2) is the student's GPA
Effects on ACT Scores
Study Hours GPA ACT Score
5 4 27
5 2 18
5 3 18
1 3 20
2 4 21
Step 1 of 2: Find the p-value for the regression equation that fits the given data. Round your answer to four decimal places.
Step 2 of 2: Determine if a statistically significant linear relationship exists between the independent and dependent variables at the 0.01 level of significance. If the relationship is statistically significant, identify the multiple regression equation that best fits the data, rounding the answers to three decimal places. Otherwise, indicate that there is not enough evidence to show that the relationship is statistically significant.
Answer:
Pvalue = 0.1505
y = 0.550x1 + 3.600x2 + 7.300
Step-by-step explanation:
Given the data :
Study Hours GPA ACT Score
5 4 27
5 2 18
5 3 18
1 3 20
2 4 21
Using technology, the Pvalue obtained using the Fratio :
F = MSregression / MSresidual = 30.228571/ 8.190476 = 3.69
The Pvalue for the regression equation is:
Using the Pvalue from Fratio calculator :
F(1, 3), 3.69 = 0.1505
Using the Pvalue approach :
At α = 0.01
Pvalue > α ; Hence, we fail to reject H0 and conclude that ; There is not enough evidence to show that the relationship is statistically significant.
The regression equation :
y = A1x1 + A2x2 +... AnXn
y = 0.550x1 + 3.600x2 + 7.300
x1 and x2 are the predictor variables ;
y = predicted variable
rewrite 1/6 and 2/11 so they have a common denominator then use <, =, or > to order
Answer:
1/6 < 2/11
Step-by-step explanation:
1/6 = 2/12
2/11 >2/12
So that means 1/6 < 2/11
Answer: 1/6 < 2/11
This is the same as saying 11/66 < 12/66
===========================================================
Explanation:
1/6 is the same as 11/66 when multiplying top and bottom by 11.
2/11 is the same as 12/66 when multiplying top and bottom by 6.
The 6 and 11 multipliers are from the original denominators (just swapped).
We can see that 11/66 is smaller than 12/66, simply because 11 < 12, so that means 1/6 is smaller than 2/11
-----------------
Here's one way you could list out the steps
11 < 12
11/66 < 12/66
1/6 < 2/11
------------------
Here's another way to list out the steps. First assume that 1/6 and 2/11 are equal. Cross multiplication then leads to
1/6 = 2/11
1*11 = 6*2
11 = 12
Which is false. But we can fix this by replacing every equal sign with a less than sign
1/6 < 2/11
1*11 < 6*2
11 < 12
---------------------
Yet another way to see which is smaller is to use your calculator or long division to find the decimal form of each value
1/6 = 0.1667 approximately
2/11 = 0.1818 approximately
We see that 0.1667 is smaller than 0.1818, which must mean 1/6 is smaller than 2/11.
Find the value of x.
Answer:
x = 3
Step-by-step explanation:
A midsegment in a trapezoid is formed when one connects the midpoints of the two legs (non-parallel sides) in a trapezoid. The midsegment theorem states that the length of the midsegment is equal to the average of the two bases (that is the parallel sides).
One can apply the midsegment theorem here by stating the following;
[tex]\frac{(YZ)+(TM)}{2}=PW[/tex]
Substitute,
[tex]\frac{23+11x+2}{2}=29[/tex]
Simplify,
[tex]\frac{25+11x}{2}=29[/tex]
Inverse operations,
[tex]\frac{25+11x}{2}=29[/tex]
[tex]25+11x=58\\\\11x = 33\\\\x = 3[/tex]
Describe the motion of a particle with position (x, y) as t varies in the given interval. (For each answer, enter an ordered pair of the form x, y.) x = 1 + sin(t), y = 3 + 2 cos(t), π/2 ≤ t ≤ 2π
Answer:
The motion of the particle describes an ellipse.
Step-by-step explanation:
The characteristics of the motion of the particle is derived by eliminating [tex]t[/tex] in the parametric expressions. Since both expressions are based on trigonometric functions, we proceed to use the following trigonometric identity:
[tex]\cos^{2} t + \sin^{2} t = 1[/tex] (1)
Where:
[tex]\cos t = \frac{y-3}{2}[/tex] (2)
[tex]\sin t = x - 1[/tex] (3)
By (2) and (3) in (1):
[tex]\left(\frac{y-3}{2} \right)^{2} + (x-1)^{2} = 1[/tex]
[tex]\frac{(x-1)^{2}}{1}+\frac{(y-3)^{2}}{4} = 1[/tex] (4)
The motion of the particle describes an ellipse.
Complete the information for that object by making estimates using appropriate units of measurement of the dimensions and by getting the actual measurements using an appropriate measuring instrument.
Answer:
hlo how are u?whats ur day is going
A large container holds 4 gallons of chocolate milk that has to be poured into bottles. Each bottle holds 2 pints.
If the ratio of gallons to pints is 1: 8,
bottles are required to hold the 4 gallons of milk.
Answer:
64 Bottles
Step-by-step explanation:
that is the procedure above
9. Mariah has 28 centimeters of reed
and 10 meters of reed for weaving
baskets. How many meters of reed
does she have? Write your answer as a
decimal and explain your answer.