Answer:
9 hours
Step-by-step explanation:
Let
x = number of hours it would take Seth to work by himself
He would paint 1/x in 1 hour
x + 2 = number of hours it would take Ted to work by himself
He would paint 1/(x + 2) in 1 hour
Seth and Ted = 5 hours
They would paint 1/5 in 1 hour
The equation is this:
1/x + 1/(x + 2) = 1/5
(x + 2)+x/x(x+2) = 1/5
x+2+x / x(x+2) = 1/5
2x + 2 / x(x+2) = 1/5
2x + 2 = x(x + 2)1/5
2x + 2 = (x² + 2x)1/5
5(2x + 2) = x² + 2x
10x + 10 = x² + 2x
x² + 2x - 10x - 10 = 0
x² - 8x - 10 = 0
x = -b ± √b² - 4ac/2a
= -(-8) ± √(-8)² - 4(1)(-10) / 2(1)
= 8 ± √64 - (-40) / 2
= 8 ± √64 + 40) / 2
= 8 ± √104 / 2
= 8 ± 2√26 / 2
= 8/2 ± 2√26/2
= 4 ± √26
= 4 ± 5.0990195135927
= 4 + 5.0990195135927 or 4 - 5.0990195135927
= 9.0990195135927 or -1.Answer:
Step-by-step explanation:
Let
x = number of hours it would take Seth to work by himself
He would paint 1/x in 1 hour
x + 2 = number of hours it would take Ted to work by himself
He would paint 1/(x + 2) in 1 hour
Seth and Ted = 5 hours
They would paint 1/5 in 1 hour
The equation is this:
1/x + 1/(x + 2) = 1/5
(x + 2)+x / x(x+2) = 1/5
x+2+x / x(x+2) = 1/5
2x + 2 / x(x+2) = 1/5
Cross product
2x + 2 = x(x + 2)1/5
2x + 2 = (x² + 2x)1/5
Cross product
5(2x + 2) = x² + 2x
10x + 10 = x² + 2x
x² + 2x - 10x - 10 = 0
x² - 8x - 10 = 0
x = -b ± √b² - 4ac/2a
= -(-8) ± √(-8)² - 4(1)(-10) / 2(1)
= 8 ± √64 - (-40) / 2
= 8 ± √64 + 40) / 2
= 8 ± √104 / 2
= 8 ± 2√26 / 2
= 8/2 ± 2√26/2
= 4 ± √26
= 4 ± 5.0990195135927
= 4 + 5.0990195135927 or 4 - 5.0990195135927
= 9.0990195135927 or -1.0990195135927
Approximately,
x = 9 hours or -1 hour
It can't take Seth negative hours to work
Therefore,
x = number of hours it would take Seth to work by himself = 9 hours
Some number times 7 is equal to the number increased by 9
Write out the equation. Do not solve the equation.
Answer:
7x = x + 9.
Step-by-step explanation:
7 × something = something + 9, right?
So, 7x = x + 9.
Approximately 10% of all people are left-handed. Consider a grouping of fifteen people.
Write the probability distribution
Answer:
Step-by-step explanation:
Answer:
15*.1=1.5
so either one or two people of the 15 would be left handed
Which ratios are less than 8 to 10? Check all that apply.
6/20
3:5
50/100
13:15
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Answer:
6/20, 3:5, 50/100 are all less than 8/10
Step-by-step explanation:
It can help to give all the ratios a common denominator. (We'll use 100, and fudge the last one a bit.)
8/10 = 80/100 . . . . our reference value
__
6/20 = 30/100 . . . less than 8/10
3/5 = 60/100 . . . . less than 8/10
50/100 . . . . . . . . . less than 8/10
13/15 ≈ 86.7/100 . . . more than 8/10
Which point is the center of the circle?
w
Opoint w
O point X
o point Y
O point Z
Answer:
X o punto Y O punto z
Step-by-step explanation:
which exponential equation is equivalent to this logarithmic equation log x5 + log x12 =7
Answer:
x⁷ = 60
Step-by-step explanation:
Given :-
log x⁵ + log x ¹² = 7 .To Find :-
The expotential equation .Solution :-
Given logarithmic equation is ,
⇒ log x⁵ + log x ¹² = 7
⇒ log x ⁵ * ¹² = 7 [ log aⁿ + log aⁿ' = log aⁿ * ⁿ' ]
⇒log x ⁶⁰ = 7
In expotential form we can write it as ,
⇒ x⁷ = 60
The standard form of an absolute value function is R(x) = a|x-h|+k Which of the following represents the vertex?
o (-k,h)
o (-1,K)
o (k,h)
o (h,k)
Answer:
o (h,k)
Step-by-step explanation:
SCALCET8 3.10.025. Use a linear approximation (or differentials) to estimate the given number. (Round your answer to five decimal places.) 3 126
Answer:
[tex]f(126) \approx 5.01333[/tex]
Step-by-step explanation:
Given
[tex]\sqrt[3]{126}[/tex]
Required
Solve using differentials
In differentiation:
[tex]f(x+\triangle x) \approx f(x) + \triangle x \cdot f'(x)[/tex]
Express 126 as 125 + 1;
i.e.
[tex]x = 125; \triangle x = 1[/tex]
So, we have:
[tex]f(125+1) \approx f(125) + 1 \cdot f'(125)[/tex]
[tex]f(126) \approx f(125) + 1 \cdot f'(125)[/tex]
To calculate f(125), we have:
[tex]f(x) = \sqrt[3]{x}[/tex]
[tex]f(125) = \sqrt[3]{125}[/tex]
[tex]f(125) = 5[/tex]
So:
[tex]f(126) \approx f(125) + 1 \cdot f'(125)[/tex]
[tex]f(126) \approx 5 + 1 \cdot f'(125)[/tex]
[tex]f(126) \approx 5 + f'(125)[/tex]
Also:
[tex]f(x) = \sqrt[3]{x}[/tex]
Rewrite as:
[tex]f(x) = x^\frac{1}{3}[/tex]
Differentiate
[tex]f'(x) = \frac{1}{3}x^{\frac{1}{3} - 1}\\[/tex]
Using law of indices, we have:
[tex]f'(x) = \frac{x^\frac{1}{3}}{3x}[/tex]
So:
[tex]f'(125) = \frac{125^\frac{1}{3}}{3*125}[/tex]
[tex]f'(125) = \frac{5}{375}[/tex]
[tex]f'(125) = \frac{1}{75}[/tex]
So, we have:
[tex]f(126) \approx 5 + f'(125)[/tex]
[tex]f(126) \approx 5 + \frac{1}{75}[/tex]
[tex]f(126) \approx 5 + 0.01333[/tex]
[tex]f(126) \approx 5.01333[/tex]
Please help!! How do I solve for x?
The line in the middle is half the length of the line on the outside. Multiply the middle line by 2 and set it equal to the outside line.
2(x-3) = x + 6
Simplify:
2x -6 p x + 6
Add 6 to both sides
2x = x + 12
Subtract x from both sides:
X = 12
The answer is B) 12
What are the values of x for which the denominator is equal to zero for y=(x+3)/(x^2+4x)
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Answer:
-4, 0
Step-by-step explanation:
The denominator is x^2+4x. This is zero when ...
x^2 +4x = 0
x(x +4) = 0
The zero product rule tells you the product is zero when the factors are zero.
x = 0
x +4 = 0 ⇒ x = -4
The denominator is zero for x=0 and x=-4.
25 x 2
help me
plz understand me by opening
Answer:
[tex]25 \times 2 = 50 \\ you \: are \: idiot \: [/tex]
really?! :|
A little help?? It’s trig
Answer:
12 [tex]\pi[/tex] = 37.699 f/s
Actually, the more interesting question
would have been how fast is the ball going in MPH?
25.7 MPH
Step-by-step explanation:
C = 2[tex]\pi r[/tex]
C = 2 [tex]* \pi * 1.2[/tex]
C = 2.4 [tex]\pi feet[/tex]
C (per second) = (5)(2.4 [tex]\pi feet[/tex])
C(per second) = 12 [tex]\pi[/tex] = 37.699 f/s
Find x. Simplify completely.
X
9
25
x = [?]
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Answer:
x = 15
Step-by-step explanation:
In this geometry, x is the geometric mean of the segment lengths of the hypotenuse.
x = √(9×25)
x = 15
would someone mind looking over my answers to geometry!!
Answer:
Question 1: x = 6
Question 2: Correct!
Question 3: x = 11
Question 4: Correct!
Step-by-step explanation:
Question 1:
Angle 22x - 2 DOESN'T equal 50 degrees. Only Alternate Interior Angles will equal each other. These two angles are Same Side Interior Angles, meaning if you added them together, they would equal 180 degrees.
Knowing that adding 22x - 2 and 50 will equals 180 degrees, here's how we solve for x:
First, subtract 50 from 180 to find what angle 22x - 2 will equal:
180 - 50 = 130
130 = 22x - 2
Now use basic algebra to solve for x:
130 = 22x - 2
(add 2 to both sides)
132 = 22x
(divide both sides by 22)
x = 6
Question 3:
Angle 5x + 15 DOESN'T equal 9x + 11. They make up a line, which is 180 degrees, so they are supplementary angles.
With that in mind, to solve for x, add the two equations and set it equal to 180:
5x + 15 + (9x + 11) = 180
Now use basic algebra to solve for x:
5x + 15 + 9x + 11 = 180
(add like terms)
14x + 26 = 180
(subtract 26 from both sides)
14x = 154
(divide 14 from both sides)
x = 11
Hope it helps (●'◡'●)
the number of cases of a new diease can be modeled by the quadratic
Step-by-step explanation:
The number of cases of a new disease may be modeled by the quadratic regression equation y=-2x^2+44x+8 , what is the best prediction for the number of cases after 20 years ( the carrot symbol (^) means the following number is the exponent)
Need help
Identify the domain of the function shown in the graph
Answer:
B
Step-by-step explanation:
I’m having trouble solving this. What’s the answer?
Find the probability of selecting 3 cards from a standard deck without
replacing them and all 3 are hearts.
Answer:
B
Step-by-step explanation:
THere are 52/4= 13 hearts we can draw
The number of ways to draw 3 hearts from 13 is
13C3= 286
The number of ways to draw 3 cards from 52 is
52C3= 22100
divide these
286/22100= 11/850
This is answer B
Use the probability distribution for the random variable x to answer the question. x 0 1 2 3 4 p(x) 0.12 0.2 0.2 0.36 0.12 Calculate the population mean, variance, and standard deviation. (Round your standard deviation to three decimal places.)
Answer:
[tex]\mu =2.16[/tex] --- Mean
[tex]\sigma^2 = 1.4944[/tex] -- Variance
[tex]\sigma = 1.222[/tex] --- Standard deviation
Step-by-step explanation:
Given
[tex]\begin{array}{cccccc}x & {0} & {1} & {2} & {3} & {4} \ \\ P(x) & {0.12} & {0.2} & {0.2} & {0.36} & {0.12} \ \end{array}[/tex]
Solving (a): The population mean
This is calculated as:
[tex]\mu = \sum x * P(x)[/tex]
So, we have:
[tex]\mu =0*0.12 + 1 * 0.2 + 2 * 0.2 + 3 * 0.36 + 4 * 0.12[/tex]
[tex]\mu =2.16[/tex]
Solving (b): The population variance
First, calculate:
[tex]E(x^2)[/tex] using:
[tex]E(x^2) = \sum x^2 * P(x)[/tex]
So, we have:
[tex]E(x^2) = 0^2*0.12 + 1^2 * 0.2 + 2^2 * 0.2 + 3^2 * 0.36 + 4^2 * 0.12[/tex]
[tex]E(x^2) =6.160[/tex]
So, the population variance is:
[tex]\sigma^2 = E(x^2) - \mu^2[/tex]
[tex]\sigma^2 = 6.16 - 2.160^2[/tex]
[tex]\sigma^2 = 6.160 - 4.6656[/tex]
[tex]\sigma^2 = 1.4944[/tex]
Solving (c): The population standard deviation
This is calculated as:
[tex]\sigma = \sqrt{\sigma^2}[/tex]
[tex]\sigma = \sqrt{1.4944}[/tex]
[tex]\sigma = 1.222[/tex]
which statements are true for the functions g(x)=x^2 and h(x)=-x^2? Check all that apply
Answer:
if x=0 then they have same value
1 and 2 options are out
for x=-1
g(-1)=1
h(-1)=-1
3 is true
4th
FALSE
for all values except 0, g(x)>h(x)
correct ones are
g(x) > h(x) for x = -1.
For positive values of x, g(x) > h(x).
For negative values of x, g(x) > h(x).
Step-by-step explanation:
54% of U.S. adults have very little confidence in newspapers. You randomly select 10 U.S. adults. Find the probability
that the number of U.S. adults who have very little confidence in newspapers is (a) exactly five, (b) at least six, and (c)
less than four.
(a) P(5) =
(Round to three decimal places as needed.)
(b) P(x26) =
(Round to three decimal places as needed.)
(c) P(x<4) =
(Round to three decimal places as needed.)
Part B is not clear and the clear one is;
P(X ≥ 6)
Answer:
A) 0.238
B) 0.478
C) 0.114
Step-by-step explanation:
To solve this, we will make use of binomial probability formula;
P(X = x) = nCx × p^(x)•(1 - p) ^(n - x)
A) 54% of U.S. adults have very little confidence in newspapers. Thus;
p = 0.54
10 random adults are selected. Thus;
P(X = 5) = 10C5 × 0.54^(5) × (1 - 0.54)^(10 - 5)
P(X = 5) = 0.238
B) P(X ≥ 6) = P(6) + P(7) + P(8) + P(9) + P(10)
From online binomial probability calculator, we have;
P(X ≥ 6) = 0.2331 + 0.1564 + 0.0688 + 0.01796 + 0.0021 = 0.47836 ≈ 0.478
C) P(x<4) = P(3) + P(2) + P(1) + P(0)
Again with online binomial probability calculations, we have;
P(x<4) = 0.1141 ≈ 0.114
Which is a correct statement about the description “two less than the quotient of a number cubed and sixteen, increased by eight” when n = 4?
Answer:
n = 4 is 10
hope it helps and have a good day
Lolz please help me I would gladly appreciate it
Pentagon has sum of 540°
Can someone help me ASAP. All them added together is = 454 .thanks
Answer:
the answer is 86°
Step-by-step explanation:
look at the photo
What is 30 percent as a fraction
Answer:
[tex] \frac{3}{10} [/tex]Step-by-step explanation:
[tex]30\% \: \: as \: fraction[/tex]
[tex] \frac{30}{100} [/tex][tex] \frac{10(3)}{10(10)} [/tex][tex] \frac{3}{10} [/tex]Hope it is helpful....Answer:
[tex] \frac{3}{10} [/tex]Step-by-step explanation:
[tex] \frac{30}{100} [/tex][tex] \frac{10(3)}{10(10)} [/tex][tex] \frac{3}{10} [/tex]- joonie
If F(x)=|x+2|+x+2, Find f(-7)
PLEASE HELP!!
what is defination of equation? And why is it called a equation.
An equation can be defined as a mathematical statement in which two expressions are set equal to each other. In simple words, equations mean equality i.e. the equal sign. Since equations are all about “equating one quantity with another”,they are simply known as equation
Answer:
In algebra, an equation can be defined as a mathematical statement consisting of an equal symbol between two algebraic expressions that have the same value. ... For instance, 3x + 5 = 14 is an equation, in which 3x + 5 and 14 are two expressions separated by an 'equal' sign.
AB is a diameter of Circle O. Find the measure of BCA
Answer:
∠ BCA = 90°
Step-by-step explanation:
∠ BCA is an angle in the semicircle and equals 90°
The probability that a certain hockey team will win any given game is 0.3669 based on their 13 year win history of 379 wins out of 1033 games played (as of a certain date). Their schedule for November contains 12 games. Let X = number of games won in November.
Required:
What is the expected number of wins for the month of November?
Answer:
4.4028
Step-by-step explanation:
Probability of game (p) = 0.3669
Number of wins in November (n) = 12
Expected number of wins = p*n
Expected number of wins = 0.3669 * 12
Expected number of wins = 4.4028
So, the expected number of wins for the month of November is 4.4028.
I need help with this question
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Answer:
x = 22, y = 123
Step-by-step explanation:
The sum of angles in a triangle is 180°.
(2x +13)° +57° +3x° = 180°
5x +70 = 180 . . . . . . . . . . . . . collect terms, divde by °
5x = 110 . . . . . . . . . . . subtract 70
x = 22 . . . . . . . . divide by 5
__
Angles in a linear pair are supplementary.
y° + 57° = 180°
y = 123 . . . . . . . . divide by °, subtract 57
Lunch break: In a recent survey of 643 working Americans ages 25-34, the average weekly amount spent on lunch as $43.21 with standard deviation $2.95. The weekly amounts are approximately bell-shaped. Part: 0 / 30 of 3 Parts Complete Part 1 of 3 Your Answer is incorrect (a) Estimate the percentage of amounts that were less than $40.26. Round the answer to one decimal place. Approximately % of the amounts were less than $40.26.
Answer:
107%
Step-by-step explanation:
Round up all possible algorithms
