Answer: If the a and b of your formula mean how many hours it takes each
person, like a = 2 and b = 1, then the formula gives 3/2 or 1 hour and
30 minutes. This is not reasonable, since one of the painters alone
could do it in 1 hour.
Actually, your formula is UPSIDE DOWN. It should be (a*b)/(a+b).
Here's why.
Let h be the number of hours it takes for the two of them to do it
together. The first person could do it all in a hours, but can paint
only a fraction of the wall working h hours. Assuming a constant rate
of painting, that fraction is h/a. That is, the first painter will
paint h/a of the wall in h hours.
Similarly, the second painter will paint h/b of the wall in that time.
So, when will they be done? When the whole wall is painted, which
happens whenever those 2 fractions add up to 1.
You need to solve the following equation:
(h/a) + (h/b) = 1
h*b + h*a = a*b Multiplying through by a*b
h*(b+a) = a*b Factoring out h
h = (a*b)/(a+b) Dividing both sides by b+a
Okay, now say 3 painters could do it in a hours, b hours or c hours,
respectively. Let h be the number of hours they all must work to get
it all painted. The first painter finishes h/a of the wall in that
amount of time. The other 2 painters manage to paint h/b of the wall
and h/c of the wall in that time. Since h is the time to finish the
job, all 3 of these fractions must add up to the whole wall, or 1.
So you have the equation:
h h h
--- + --- + --- = 1
a b c
Solve this for h (start by multiplying through by a*b*c) and you will
get the generalized formula for 3 painters. It's not the formula you
wrote above but I think you can finish it off.
(I hope this helps. I'm sorry if it's wrong)
2 3/4 2 11/12 in simplist form
Answer:
2 9/12 and 2 11/12
Step-by-step explanation:
if that is what u are asking. simplist form is 2 3/4 and 2 11/12.
Hope that helps and good luck :)
Which expression uses commutative property to make it easier to evaluate
2/3 * 1/4 * 27
Answer:
2/3 x 27 x 1/4
Step-by-step explanation:
A-P-E-X
What is the sum of 4.3943 and 5.4157?
A.9.71
C. 9.81
B.9.72
D.9.82
Answer:
9.81
Step-by-step explanation:
You have to add them up: 4.3943 +
5.4157
----------
9.8100
Point R on the coordinate grid below shows the location of a car in a parking lot. A second car needs to park 6 units above R to leave room for a utility truck. What are the coordinates of the location of the second car?
Image of a coordinate grid with point R R located at negative 1, negative 3.
(3 points)
(−1, −3)
(−1, 3)
(5, −3)
(5, 3)
Answer:
Point R is located at the point (-1,-3)
The car needs to park 6 units above point R.
When you are moving something up or down on the coordinate grid, you are affecting the y- axis. So to find the coordinates we would keep the x value and add 6 to the y value.
Coordinates of the second car
(-1, -3 +6)
(-1 , 3)
The answer to this question is B
Adding a positive to a negative is the same as subtracting.
EX:
We were adding 6 and -3
Adding 6 and -3 is the same as subtracting 3 from 6.
Either way we get the same answer.
B is your answer
Hope this helps!
Devin volunteers at Big Pup Rescue. He is mixing up shampoo solution for the dog washing station. He needs 2 cups of shampoo concentrate for every 9 cups of water. Devin will use 36 cups of water.
How much shampoo concentrate should Devin add to the water to make the shampoo solution?
Answer:
8 cups of shampoo concentrate
Step-by-step explanation:
let x=how much shampoo concentrate Devin should add
[tex]\frac{2}{9} =\frac{x}{36}[/tex]
cross multiply
2*36=9x
72=9x
72/9=x
x=8
Devin should add 8 cups of shampoo concentrate to the water to make the shampoo solution.
In triangle XYZ, angle Y = 45º and angle Z = 60º. If XZ = 4, then what is XY?
Answer:
[tex]XY = 4.9[/tex]
Step-by-step explanation:
Given
[tex]XZ= 4[/tex]
[tex]\angle Y = 45[/tex]
[tex]\angle Z = 60[/tex]
Required
Determine the measure of side XY
To do this, we make use of sine law. This is as follows:
[tex]\frac{a}{\sin\ A} = \frac{b}{\sin\ B} = \frac{c}{\sin\ C}[/tex]
In this case:
[tex]\frac{4}{\sin(45)} = \frac{XY}{\sin(60)}[/tex]
Cross Multiply
[tex]XY * \sin(45) = 4 * \sin(60)[/tex]
[tex]XY * 0.7071 = 4 * 0.8660[/tex]
Make XY the subject
[tex]XY = \frac{4 * 0.8660}{0.7071}[/tex]
[tex]XY = \frac{3.4640}{0.7071}[/tex]
[tex]XY = 4.89888276057[/tex]
[tex]XY = 4.9[/tex] -- approximated
Which equation has a slope of 2 and y-intercept of -3
y = 2x -3
fhfjdydtsfxbnpurwsgh
3/5 c = 9 what is the answer
Quincy rides his bicycle 1 mile in 4 minutes, and his sister Marissa runs 13,376 feet in 16 minutes. In miles per hour approximately how much faster is Quincy than Marissa? (Note: 1 mile = 5,280 feet)
Answer:
Quincy is 5.5 mi/h faster than Marissa
Step-by-step explanation:
Speed
It's required to compare the speed of Quincy and Marissa knowing that Quincy rides his bicycle 1 mile in 4 minutes.
The speed can be calculated as the distance by the time, but it's required to express the speed in miles/hour.
4 minutes is 4/60 = 0.0667 hours, thus Quincy's speed is:
[tex]\displaystyle \frac{1\ mile}{0.0667\ h}=15\ mi/h[/tex]
Quincy rides at 15 miles/hour.
Marissa runs 13,376 feet in 16 minutes. Since 1 mile=5,280 feet:
13,376 / 5,280 = 2.533 miles
16 minutes = 16/60 = 0.2667 hours
Marissa's speed is:
[tex]\displaystyle \frac{2.533\ mile}{0.2667 \ h}=9.5\ mi/h[/tex]
The difference is 15 - 9.5 = 5.5 mi/h
Quincy is 5.5 mi/h faster than Marissa
The data below gives the mean price (in cents) of a liter of regular gasoline at self-service filling stations at a sample of six urban centers in Canada in May 2011.
Urban area Price/liter
St. John, NL 137.1
Halifax 133.6
Montreal 136.2
Regina 132.3
Saskatoon 132.2
Yellowknife 138.9
Required:
a. Find the sample mean (in cents).
b. Find the sample standard deviation (in cents).
c. Find a 90% confidence interval for the mean gasoline price per liter across urban Canada in May 2011. Provide the lower and upper limits for your confidence interval.
d. Find a 95% confidence interval for the mean gasoline price per liter across urban Canada in May 2011. Provide the lower and upper limits for your confidence interval.
Answer:
135.05 ; 2.762 ; (133.201, 136.899) ; (132.840, 137.260)
Step-by-step explanation:
Given the data:
Urban area Price/liter
St. John, NL 137.1
Halifax 133.6
Montreal 136.2
Regina 132.3
Saskatoon 132.2
Yellowknife 138.9
Mean = (137.1 + 133.6 + 136.2 + 132.3 + 132.2 + 138.9) / 6
= 810.3 / 6
= 135.05
Standard deviation (σ) : √Σ(X - mean)²/n-1
(137.1 - 135.05)^2 + (133.6 - 135.05)^2 + (136.2 - 135.05)^2 + (132.3 - 135.05)^2 + (132.2 - 135.05)^2+ (138.9 - 135.05)^2 = 38.135
√(38.135 / (6 - 1))
= √7.627
= 2.7617023
= 2.762
C.)
90% confidence interval of the mean :
Mean ± Zcrit * σ/√n
Zcrit at 90% = 1.64
135.05 ± 1.64 * (2.762/√6)
135.05 ± 1.64 * 1.1275817
Lower Value = (135.05 - (1.64 * 1.1275817)) = 133.201
Upper Value = (135.05 + (1.64 * 1.1275817))) = 136.899
Confidence interval = (133.201, 136.899)
D.)
95% confidence interval of the mean :
Mean ± Zcrit * σ/√n
Zcrit at 95% = 1.96
135.05 ± 1.96 * (2.762/6)
135.05 ± 1.96 * 1.1275817
Lower Value = (135.05 - (1.96 * 1.1275817)) = 132.840
Upper Value = (135.05 + (1.96 * 1.1275817)) = 137.260
Confidence interval = (132.840, 137.260)
Find all missing angles
Answer:
m1=30
m2=41
m3=96
Step-by-step explanation:
m1=180-66-84
m2=180-96-43
m3=180-84
What is the solution for this inequality?
need help fast please!
Answer:
[tex]x\geq -4[/tex]
Step-by-step explanation:
[tex]-10x\leq 40[/tex]
divide by -10, which means you need to flip the inequality sign since youre dividing by a negative number
[tex]x\geq -4[/tex]
Answer:
The anwer is D
Step-by-step explanation:
up up up......
what is the slope of the line on the graph below?
answers: a -1/2. b 1/2. c 1. d 2
please help!
Answer:
D
Step-by-step explanation:
work out the difference in minutes between 1 hour 25 minutes and 1 1/4
Answer:
1 1/4 is 10 minutes less than 1 hour and 25 minutes
Step-by-step explanation:
1 1/4 is equivalent to 1 hour and 15 minutes.
We get this by taking the 60 minutes we know are in an hour and multiplying it by the 1/4
[tex]\frac{60}{1} *\frac{1}{4} = \frac{60}{4} = 15[/tex]
The difference between 25 minutes and 15 minutes is 10 minutes.
6 ×3(2+9)..can you give the answer of it please
Answer:
Hope this may helps you
Step-by-step explanation:
6×3(11)
6×33
198
Answer:
198
Step-by-step explanation:
6 ×3(2+9)
= 6×3×11
= 6×33
= 198
What is the y-intercept of the graph of 4y = 2x + 8?
4
2
6
00
N
Answer:
2
Step-by-step explanation:
4y = 2x + 8
First get the equation in slope intercept form y= mx+b where m is the slope and b is the y intercept
Divide each side by 4
4y/4 = 2x/4 +8/4
y = 1/2x +2
The slope is 1/2 and the y intercept is 2
Answer:
2
Step-by-step explanation:
Manipulate your equation into slope-intercept form: y = mx + b, where b is the y-intercept.
To do this, divide 4 from both sides:
[tex]y=\frac{1}{2} x+2[/tex]
b = 2
The perimeter of the square below is 36 yards. What is the length of each side?
yards
Answer:
9 yards
Step-by-step explanation:
36 divided by 4 = 9
The length of each side is 9 yards.
What is perimeter?A closed shape's perimeter is the sum of the lengths of its outside boundaries. The lengths of all the sides are added to determine the measurement.
Given:
The perimeter of the square below is 36 yards.
The length of each side,
= perimeter/ number of sides.
= 36/4
= 9 yards.
Therefore, each side is 9 yards.
To learn more about the perimeter of a shape:
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Devon is building a shed and ordered lumber from a local shop. When the lumber was delivered it was placed in a 24 inch high stack. If each board is
1 1/2
inches thick, how many boards are stacked up?
NEED HELP ASAP:)
16 cause 24 divided by 1 1/2= 16
Solve each system using substitution.
1. 4x= 3y-2 ; 18= 3x+y
Answer:
y = 6
Step-by-step explanation:
so since you have 2 variables, you need to find a substitution for one of them.
let's do that for y
let y = something in the second equation.
y = 18 - 3x
then plug this into the first equation
4x = 3(18 - 3x) - 2
4x = 54 - 9x -2
4x = 52 - 9x
13x = 52
x = 4
now you have x, plug it into any of the equations to find y.
4(4) = 3y - 2
16 = 3y - 2
18 = 3y
y = 6
Answer:
x = 4, y = 6
Step-by-step explanation:
Substituting y into 1:
4x= 3y-2 -----1
18= 3x+y -----2
Isolate the y in 2.
y = 18-3x -----3
Substitute 3 into 1.
4x= 3(18-3x)-2
Evaluate.
4x = 54-9x-2
Keep like terms together.
4x+9x = 54-2
Simplify.
13x = 52
Find x.
x = 52 ÷ 13
= 4
Substitute x into 3.
y = 18-3(4)
Evaluate.
y = 18-12
Find y.
y = 6
When the price of Xis RM4 and the price of Y is RM10, which of the following combinations would be the intercept of axes
(X,Y) if you have an income of RM 100?
Select one:
A. (25X, 10Y)
B. (20X, 5Y)
C. (10X, 25Y)
D. (5X, 20Y)
2.
Mrs Yusuf went shopping at a superstore.
The pie chart shows information about the money she spent on petrol, on clothes, on food and on
other items
Puro
bao
Food
Clothes
(a) What did she spend most money on?
Answer:
Dude First show the pie chart
Mrs. Yusuf spend the most money on Food.
Given is pie chart showing the information about the money Mrs. Yusuf spent on petrol, on clothes, on food and on other items,
We need to identify the portion which tell that she spend the most money on that item,
So, we know that the more portion one item has on the pie chart the more she had spend on that item,
Here in the pie chart we can see the food portion is largest.
So, we can say she spend her most money on food items.
Hence the correct answer is Food.
Learn more about Pie chart click;
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ANYONE WANNNA HELP MATH!!!!! HRW BTW
Answer:
1/4 off
Step-by-step explanation:
1/4 is 0.25. 0.25 times 100 is 25. It would be 25% off. 25 is more than 20 and why buy 3 to get 1 free. Hope this helps!!!! Let me know if i'm right please.
Find the possible range of c
Answer:
53
Step-by-step explanation:
trust me
NEED HELP ASAP!!!! WILL MARK BRAINLIEST!!!!!
Which statement best compares the rate of change of the two functions?
O The rate of change of both functions is 2
O The rate of change of both functions is 3.
O The rate of change of function A is greater. than the rate of change of function B.
O The rate of change of function B is greater than the rate of change of function A.
Answer: The rate of change is 2
Step-by-step explanation:
Divide the Y by X for each of them and they all are 2
Why is it a good idea to check to see if your answer is reasonable?
a. if your answer is reasonable, you have
b. if you understand the problem, you will not need to check your answer.
c. you just need to solve for the varible
d. to get the correct answer, you will need to need to check your answer draw a picture
Please select the best answer from the choices provided.
Answer:
D number option is the correct answer
Answer:
A. if your answer is reasonable, you have probably done the problem correctly
Step-by-step explanation:
A partnership between two companies calls for company A to get a flat fee of $25,000 from Company B each month, plus 15% of all sales for the jointly developed product sold by company B. If Company B sells a total of $1,200,000 of the jointly developed product in the first twelve months, what will be the total amount owed Company A by Company B?
Answer:
no idea what the answer is, good luck!
Step-by-step explanation:
A 5 lb. package of chicken costs $6.00. What is the cost per pound?
Answer:
$1.2
Step-by-step explanation:
Cost per pound = 6/5 = $1.2
Answer:
1.20 a pound
Step-by-step explanation:
The seventh grade class is having a dance. They are selling tickets for $8 each. How many tickets do they need to sell to pay for their expenses, which equal $256?
Answer:
They need to sell 32 tickets
Step-by-step explanation:
256/8=32
Answer:
They need to sell 32 tickets to pay for their expenses.
Is this a function?
Answer:
yes
Step-by-step explanation:
what is m% of n please help
m% of n would technically be some amount of n. To find m%, you would have to do n * 0.m to find your answer