The chance of winning the race of the horse A is 1/15 and that of horse B is 1/6. What is
the probability that the race will be won by A or B.

Answers

Answer 1

Answer:

7/30

Step-by-step explanation:

P = 1/15 + 1/6 = (2+5)/30 = 7/30


Related Questions

a bag contain 3 black balls and 2 white balls.
1. A ball is taken from the black and then replaced, a second is taken. what is the probabilities that.

(a) there are both black,
(b)one is black one is white,
(c) at lease one is black,
(d) at most one is one is black.

2. find out if all the balls are chosen without replacement.

please kindly solve with explanation. thank you.​

Answers

Answer:

Step-by-step explanation:

Total number of balls = 3 + 2 = 5

1)

a)

[tex]Probability \ of \ taking \ 2 \ black \ ball \ with \ replacement\\\\ = \frac{3C_1}{5C_1} \times \frac{3C_1}{5C_1} =\frac{3}{5} \times \frac{3}{5} = \frac{9}{25}\\\\[/tex]

b)

[tex]Probability \ of \ one \ black \ and \ one\ white \ with \ replacement \\\\= \frac{3C_1}{5C_1} \times \frac{2C_1}{5C_1} = \frac{3}{5} \times \frac{2}{5} = \frac{6}{25}[/tex]

c)

Probability of at least one black( means BB or BW or WB)

 [tex]=\frac{3}{5} \times \frac{3}{5} + \frac{3}{5} \times \frac{2}{5} + \frac{2}{5} \times \frac{3}{5} \\\\= \frac{9}{25} + \frac{6}{25} + \frac{6}{25}\\\\= \frac{21}{25}[/tex]

d)

Probability of at most one black ( means WW or WB or BW)

[tex]=\frac{2}{5} \times \frac{2}{5} + \frac{3}{5} \times \frac{2}{5} \times \frac{2}{5} + \frac{3}{5}\\\\= \frac{4}{25} + \frac{6}{25} + \frac{6}{25}\\\\=\frac{16}{25}[/tex]

2)

a) Probability both black without replacement

  [tex]=\frac{3}{5} \times \frac{2}{4}\\\\=\frac{6}{20}\\\\=\frac{3}{10}[/tex]

b) Probability  of one black and one white

 [tex]=\frac{3}{5} \times \frac{2}{4}\\\\=\frac{6}{20}\\\\=\frac{3}{10}[/tex]

c) Probability of at least one black ( BB or BW or WB)

 [tex]=\frac{3}{5} \times \frac{2}{4} + \frac{3}{5} \times \frac{2}{4} + \frac{2}{5} \times \frac{3}{4}\\\\=\frac{6}{20} + \frac{6}{20} + \frac{6}{20} \\\\=\frac{18}{20} \\\\=\frac{9}{10}[/tex]

d) Probability of at most one black ( BW or WW or WB)

 [tex]=\frac{3}{5} \times \frac{2}{4} + \frac{2}{5} \times \frac{1}{4} + \frac{2}{5} \times \frac{3}{4}\\\\=\frac{6}{20} + \frac{2}{20} + \frac{6}{20} \\\\=\frac{14}{20}\\\\=\frac{7}{10}[/tex]

please help will mark brainly!!!!! need done. PERSONAL FINANCE

Answers

Answer:

Step-by-step explanation:

-6×-5y=6
4x+y=3
What's answer to this equation

Answers

9514 1404 393

Answer:

  (x, y) = (3/2, -3)

Step-by-step explanation:

Using the second equation, we can write an expression for y:

  y = 3 -4x

Using this in the first equation, we have ...

  -6x -5(3 -4x) = 6

  -6x -15 +20x = 6 . . . . eliminate parentheses

  14x = 21

  x = 21/14 = 1.5

  y = 3 -4(1.5) = 3 -6 = -3

The solution is (x, y) = (1.5, -3).

__

I find a graphing calculator a useful tool for finding solutions quickly.

The dress store is having a sale where all merchandise is 1/4 off. A woman buys $48 of merchandise at a sale price.

Answers

Answer:$36 depending on what question is i just assuming how much she has to pay

Step-by-step explanation:

48 divded by 4 is 12. $48-$12 is $36. The $12 is the 1/4 discount.

the admission fee for a charity event is $7 for children and 10$ for adults. The event was attended by 700 people, and the total amount collected in admissions was $6,400.

Answers

Answer:

200 kids and 500 adults

Step-by-step explanation:

x+y=700

7x+10y=6,400

(200,500)

kids=200

adults=500

How and what is the value of X?

Answers

Answer:

9 =x

Step-by-step explanation:

The angles are vertical angles and vertical angles are equal

56 = 6x+2

Subtract 2 from each side

56-2 = 6x+2-2

54 = 6x

Divide each side by 6

54/6 = 6x/6

9 =x

An internet cafe charges a fixed amount per minute to use the internet. The cost of using the
internet in dollars is, y = 3/4x. If x is the number of minutes spent on the internet, how many
minutes will $6 buy?
er

Answers

Answer:

x = 8 minutes

Step-by-step explanation:

Given that,

An internet cafe charges a fixed amount per minute to use the internet.

The cost of using the  internet in dollars is,

[tex]y=\dfrac{3}{4}x[/tex]

Where

x is the number of minutes spent on the internet

We need to find the value of x when y = $6.

So, put y = 6 in the above equation.

[tex]6=\dfrac{3}{4}x\\\\x=\dfrac{6\times 4}{3}\\\\x=8\ min[/tex]

So, 8 minutes must spent on internet.

A walking path across a park is represented by the equation y = -4x + 10. A new path will be built perpendicular to this path. The paths will intersect at the point (4, -6). Identify the equation that represents the new path.

Answers

Answer:  [tex]y=\frac{1}{4}x-7[/tex]

Step-by-step explanation:

The perpendicular slope of the line(m) = [tex]-\frac{1}{m}[/tex]:

m = -4 ⇒ [tex]-\frac{1}{m} =-\frac{1}{(-4)} =\frac{1}{4}[/tex]

The function formula is y = mx + b, where the y-intercept(b) is found by substituting in the values of a point on the line ⇒ (4, -6):

[tex]y=\frac{1}{4}x+b\\-6=\frac{1}{4}(4)+b\\-6=1+b\\b=-6-1=-7[/tex]

So the perpendicular equation is [tex]y=\frac{1}{4}x-7[/tex].

whitch numbre produces a rational number when multiplied by 1/3 ?

Answers

Answer:

Step-by-step explanation:

multiplication of two rational numbers produce a rational number.


Work out the surface area of this sphere.
Give your answer to 1 decimal place.
Spheres
Surface area =
4tr?
6 cm

Answers

Answer:

452.2 cm

Step-by-step explanation:

A = 4πr²

A = 4 (3.14) (6)²

A = 4 (3.14) (36)

A = 452.16

A = 452.2 cm (nearest tenth)

A Roper survey reported that 65 out of 500 women ages 18-29 said that they had the most say when purchasing a computer; a sample of 700 men (unrelated to the women) ages 18-29 found that 133 men said that they had the most say when purchasing a computer. What is the 99% confidence interval for the difference of the two proportions

Answers

Answer:

[tex]Z=-2.87[/tex]

Step-by-step explanation:

From the question we are told that:

Probability on women

[tex]P(W)=65 / 500[/tex]

[tex]P(W) = 0.13[/tex]

Probability on women

[tex]P(M)=133 / 700[/tex]

[tex]P(M) = 0.19[/tex]

Confidence Interval [tex]CI=99\%[/tex]

Generally the equation for momentum is mathematically given by

[tex]Z = \frac{( P(W) - P(M) )}{\sqrt{(\frac{ \sigma_1 * \sigma_2 }{(1/n1 + 1/n2)}}})[/tex]

Where

[tex]\sigma_1=(x_1+x_2)(n_1+n_2)[/tex]

[tex]\sigma_1=\frac{( 65 + 133 )}{ ( 500 + 700 )}[/tex]

[tex]\sigma_1=0.165[/tex]

And

[tex]\sigma_2=1 - \sigma = 0.835[/tex]

Therefore

[tex]Z = \frac{( 0.13 - 0.19)}{\sqrt{\frac{( 0.165 * 0.835}{ (500 + 700) )}}}[/tex]

[tex]Z=-2.87[/tex]

13. Given that
[tex] {x}^{2} + {y}^{2} + 10y + 16 = 0[/tex]
and
[tex] {(x - 3)}^{2} + {y}^{2} = 1[/tex] are two circles on the same plane. Find:
a) the coordinates of the center and the radius for each circle.
b) the equation of the straight line joining the center of both circles.​

Answers

step by step explanation:

[tex]\mathfrak{x}^{2}+{y}^{2}+16=0[/tex]

=[x2+16=0x26]

=[2x{y}^2{16}~0]

=[4×{y}^0{16}]

=[32x{y}^x]

The manager of a fast-food restaurant determines that the average time that her customers wait for service is 2.5 minutes. (a) Find the probability that a customer has to wait more than 4 minutes. (Round your answer to three decimal places.)

Answers

Answer:

0.758

explaination

using poisson distribution

0.08208+0.2052+0.2565+0.2138

0 .758

is y=3x^2-x-1 a function

Answers

Answer: Yes it is a function.

This is because any x input leads to exactly one y output.

The graph passes the vertical line test. It is impossible to draw a single vertical line through more than one point on the parabolic curve.

What is the correct definition for sec theta?

Answers

Answer:

D Is the correct answer Thats was too easy

Answer:

sec(θ) = hypotenuse / adjacent.

Step-by-step explanation:

sec theta= cos -1  theta

3x+4 number of terms

Answers

9514 1404 393

Answer:

  2

Step-by-step explanation:

In this expression, the terms are the parts of the sum. They are 3x and 4. There are 2 terms.

We have a study involving 5 different groups that each contain 9 participants (45 total). What two degrees of freedom would we report when we report the results of our study

Answers

Answer:

Degree of freedoms F(4,40)

Step-by-step explanation:

Given:

There is a study which is involving 5 different groups that each contains 9 participants (totally 45)

The objective is to calculate the degree of freedoms

Formula used:

Numerator degree of freedom = k-1

denominator degree of freedom=N-K

Solution:

Numerator degree of freedom = k-1

denominator degree of freedom=N-K

Where,

K= number of groups = 5

N= total number of observations

which is given as follows,

N=45

Then,

Numerator degree of freedom = k-1

=5-1

=4

Denominator degree of freedom = N-K

=45-5

=40

Therefore,

Degree of freedoms, F(4,40)

Find a degree 3 polynomial with real coefficients having zeros 1
and 2−2i and a lead coefficient of 1. Write P in expanded form. Be sure to write the full equation, including P(x)=

Answers

9514 1404 393

Answer:

  P(x) = x³ -5x² +12x -8

Step-by-step explanation:

If the coefficients are real, then the complex roots must be conjugates. The third root is 2+2i. For root r, (x -r) is a factor, so the factorization is ...

  P(x) = (x -1)(x -2 +2i)(x -2 -2i) = (x -1)((x -2)² +4) = (x -1)(x^2 -4x +8)

Expanding further, we find ...

  P(x) = x³ -5x² +12x -8

what is nine and three hundred twenty-one thousandths in decimal notation?

Answers

Answer:

Step-by-step explanation:

9.0321 ? Im not sure but i tried

If a:b = 1:2 then find the value of (3a + b): (4a + 2b).​

Answers

Answer:

5:8

Step-by-step explanation:

By question it's given that ,

[tex]\implies a:b = 1:2 [/tex]

Let us suppose that the common ratio is x , therefore the Numbers ,

[tex]\implies a = 1x [/tex]

[tex]\implies b = 2x [/tex]

And we need to find the value of ,

[tex]\implies (3a + b): (4a + 2b ) \\\\\implies (3 * x + 2x ) : (4*x + 2*2x ) \\\\\implies (3x + 2x):(4x+4x)\\\\\implies 5x : 8x \\\\\implies 5:8 [/tex]

Hence the required answer is 5:8 .

x^2-9x+20 the factor of this trinomial are(____)(___)

Answers

Answer:

(x-4) (x-5)

Step-by-step explanation:

* means multiply

first you figure out what 2 numbers

when added make 9

when multiplied make 20

those are 4 and 5

(x  4) (x  5)

in this case

-4 -5 make -9

-4 * -5 make 20

(x-4) (x-5)

Answer:

(x-4)(x-5)

Step-by-step explanation:

Firstly you need to use the second equation formula to get the value of x.

x= [tex]\frac{-(-9)+- \sqrt{(-9)^{2}-4*1*20 } }{2*1}[/tex]

x= [tex]\frac{9+- \sqrt{81-80 } }{2}[/tex]

x= [tex]\frac{9+-1}{2}[/tex]

so,

x=[tex]\frac{9+1}{2}[/tex]      x=5

and

x=[tex]\frac{9-1}{2}[/tex]      x=4

When writing the factor, we have to change signs of 5 and 4. So it will be -5 and -4.

That's why the awnser is (x-4)(x-5)

Hope it helps!

rom each corner of a square piece of sheet metal 18 centimeters on a side,we remove a small square and turn up the edges to form an open box. Whatis the largest volume this box could have

Answers

Answer:

The volume is maximum when the height is 3 cm.

Step-by-step explanation:

let the side of the removed potion is x.

length of the box = 18 - 2 x

width of the box = 18 - 2 x

height = x

Volume of box

V = Length x width x height

[tex]V = (18 - 2 x)^2 \times x\\\\V = x(324 + 4x^2 - 72 x)\\\\V = 4 x^3 - 72 x^2 + 324 x \\\\\frac{dV}{dx} = 12 x^2 - 144 x + 324 \\\\So,\\\\ \frac{dV}{dx} =0\\\\x^2 - 12 x + 27 = 0 \\\\x^2 -9 x - 3 x + 27 =0\\\\x (x - 9) - 3 (x -9) = 0\\\\x = 3, 9[/tex]

Now

[tex]\frac{d^2V}{dx^2}=24 x - 144 \\\\Put x = 3 \\\\\frac{d^2V}{dx^2}=24\times 3 - 144 = - 72\\\\Put x = 9\\\\\frac{d^2V}{dx^2}=24\times 9 - 144 = 72\\[/tex]

So, the volume is maximum when x = 3 .

Write the following using algebraic notation, using the letter x for any
unknown numbers:
I think of a number, double it, then add fifteen.

Answers

You do X2 + 15 and that will be your answer.

By the way, the 2 is a power and is meant to be smaller on top of the X.

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.

Answers

10.28 , 28 cm in meters is 0.28. you have 10 meters therefore 10+.28= 10.28

Blank DVD's are sold in packages of 50 for $17.95 if your company will need 2700 blank divide these next year how much money must your budget for blank dvd's

Answers

Answer:

Step-by-step explanation:

50 X 240 = 2700. So you will need 240 packs of 50. They cost 17.95 each, so the multiply. 240 X 17.95 is 4,308. So, 4,308 is your answer.

There is a bag with only red marbles and blue marbles.
The probability of randomly choosing a red marble is
7/10th


There are 42 red marbles in the bag and each is equally likely to be chosen.
Work out how many marbles in total there must be.

Answers

Answer:

60 marbles in total

Step-by-step explanation:

Find how many marbles there are in total by dividing 42 by 0.7:

42/0.7

= 60

So, there are 60 marbles in total

A forestry researcher wants to estimate the average height of trees in a forest near Atlanta, Georgia. She takes a random sample of 18 trees from this forest. The researcher found that the average height was 4.8 meters with a standard deviation of 0.55 meters. Assume that the distribution of the heights of these trees is normal. For this sample what is the margin of error for her 99% confidence interval

Answers

Answer:

The margin of error for her confdence interval is of 0.3757.

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 18 - 1 = 17

99% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 17 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.99}{2} = 0.995[/tex]. So we have T = 2.8982

The margin of error is:

[tex]M = T\frac{s}{\sqrt{n}}[/tex]

In which s is the standard deviation of the sample and n is the size of the sample.

Standard deviation of 0.55 meters.

This means that [tex]s = 0.55[/tex]

What is the margin of error for her 99% confidence interval?

[tex]M = T\frac{s}{\sqrt{n}}[/tex]

[tex]M = 2.8982\frac{0.55}{\sqrt{18}}[/tex]

[tex]M = 0.3757[/tex]

The margin of error for her confdence interval is of 0.3757.

Margin of error is the distance between the mean and the limit of confidence intervals. The margin of error for the given condition is 3.28 approximately.

What is the margin of error for small samples?

Suppose that we have:

Sample size n  < 30

Sample standard deviation = sPopulation standard deviation = [tex]\sigma[/tex]Level of significance = [tex]\alpha[/tex]Degree of freedom = n-1

Then the margin of error(MOE) is obtained as

Case 1: Population standard deviation is known

Margin of Error = [tex]MOE = T_{c}\dfrac{\sigma}{\sqrt{n}}[/tex]

Case 2: Population standard deviation is unknown

[tex]MOE = T_{c}\dfrac{s}{\sqrt{n}}[/tex]

where [tex]T_{c}[/tex] is critical value of the test statistic at level of significance

For the given case, taking the random variable X to be tracking the height of trees in the sample taken of trees from the considered forest.

Then, by the given data, we get:

[tex]\overline{x} = 4.8[/tex], [tex]s = 4.8[/tex], n = 18

The degree of freedom is n-1 = 17

Level of significance = 100% - 99% = 1% = 0.01

The critical value of t at level of significance 0.01 with degree of freedom 17 is obtained as T = 2.90 (from the t critical values table)

Thus, margin of error for 99% confidence interval for considered case is:

[tex]MOE = T_{c}\dfrac{s}{\sqrt{n}}\\\\MOE = 2.9 \times \dfrac{4.8}{\sqrt{18}} \approx 3.28[/tex]

Thus, the margin of error for the given condition is 3.28 approximately.

Learn more about margin of error here:

https://brainly.com/question/13220147

Which function has the following characteristics?


- A vertical asymptote at x=3

- A horizontal asymptote at y=2

- Domain: {x ≠ ±3}


A. y= (2x-8) / (x-3)

B. y= (2x^2 - 8) / (x^2 - 9)

C. y= (x^2 - 9) / (x^2 - 4)

D. y= (2x^2 - 18) / (x^2 - 4)

Answers

The function has the characteristics is (b) y= (2x^2 - 8) / (x^2 - 9)

How to determine the function?

The features are given as:

A vertical asymptote at x=3A horizontal asymptote at y=2Domain: {x ≠ ±3}

The function that has the above features is (b).

This is proved as follows:

y= (2x^2 - 8) / (x^2 - 9)

Set the denominator not equal to 0, to determine the domain

x^2 - 9 ≠ 0

Add 9 to both sides

x^2 ≠ 9

Take the square roots

x ≠ ±3 --- domain

Replace ≠ with =

x = ±3 --- vertical asymptote

Set the numerator to 0

2x^2 - 8 = 0

Divide through by 2

x^2 - 4 = 0

This gives

x^2 = 4

Take the square roots

x = 2 ---- horizontal asymptote

Hence, the function has the characteristics is (b) y= (2x^2 - 8) / (x^2 - 9)

Read more about functions at:

https://brainly.com/question/4138300

#SPJ1

i need help with these questions. anyone down to help me ?please

Answers

9514 1404 393

Answer:

A: less than 2 hoursB: 2 to 5 hoursC: more than 5 hours

Step-by-step explanation:

The attached graph shows the various company costs for x number of hours. The graph nearest the x-axis represents the lowest cost.

We can see that cost is lowest using Company A for 2 hours or less, and Company C for 5 hours or more. For times between those, Company B has the lowest charges.

Of course, the equation for charges in each case is the sum of the service fee and the product of hourly charge and number of hours (x).

__

I find the graphing calculator to be the most efficient tool for solving these. The alternative is to compare the equations pairwise to see which gives lower rates. With a little practice, you learn that the "break even hours" will be the difference in service fees divided by the difference in hourly cost.

For example A will cost the same as B when the $20 service fee and the $10/hour cost difference are the same: for 2 hours. A and C will cost the same when the $45 service fee and the $15/hour cost difference are the same, after 3 hours. B and C will cost the same when the $25 difference in service fees and the $5/hour cost difference are the same, after 5 hours.

So B is cheaper above 2 hours, and C is cheaper than that above 5 hours. With no service fee, A is cheaper for small numbers of hours (<2).

You want to make a playlist with all different songs. How many ways can you make a playlist of 16 songs if you must play Leavon, Dream on, Here Comes the Sun, and Clocks in that order?

Answer in permutations

Answers

Answer:  [tex]_{13} P _{13}[/tex]

Another acceptable answer is 13! where the exclamation mark is needed.

The numeric form is 6,227,020,800 which is a little over 6 billion.

==============================================================

Explanation:

Let's lump those four songs together to form a so called "mega song". So we treat those four items as one single item. This is ensure that those songs are played in the order we want. The other songs aren't treated this way.

We start with 16 songs and drop to 16-4 = 12 songs when taking out those four named songs. Then we add 1 to get 12+1 = 13 since we're adding in that "mega song" block.

---------------------------

So to recap so far, we've gone from 16 songs to 13 songs. The goal is to find out how many arrangements of 13 songs are possible. Order matters.

We'll use the nPr permutation function

[tex]_{n} P _{r} = \frac{n!}{(n-r)!}\\\\[/tex]

where in this case n = 13 and r = 13. Your teacher doesn't want you to evaluate this function. You simply need to state the symbolic form. So that's why we go from [tex]_{n} P _{r}[/tex] to [tex]_{13} P _{13}[/tex]

If you wanted to answer this in terms of factorial notation, then you could say this

[tex]_{n} P _{r} = \frac{n!}{(n-r)!}\\\\_{13} P _{13} = \frac{13!}{(13-13)!}\\\\_{13} P _{13} = \frac{13!}{(0)!}\\\\_{13} P _{13} = \frac{13!}{1}\\\\_{13} P _{13} = 13!\\\\[/tex]

So we can see that the notations [tex]_{13} P _{13}[/tex] and [tex]13![/tex] mean the exact same thing.

If you wanted to know the actual number of permutations, then,

13! = 13*12*11*10*9*8*7*6*5*4*3*2*1 = 6,227,020,800

which is a little over 6 billion permutations.

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