Please help! Answer and explanation please!

Please Help! Answer And Explanation Please!

Answers

Answer 1

Answer:

12

Step-by-step explanation:

Since we can infer that those lines are the same length...

5x-15 = 3x+9

2x -15 = 9

2x = 24

x = 12


Related Questions

Can y’all help me on question 27?!

Answers

Answer:

B and D

Step-by-step explanation:

A would be:

57 + 2j

C would be:

13-t

Lucy and Ayu sold a total of 1,080 iPads. Lucy sold 7 times as many as Ayu. How many did each sell

Answers

Answer:

let L=lucy and A=ayu

l+a=1080

l=7a 7a+a=1080

8a=1080 8a/8=1080/8

ayu=135

l=7a l=7×135

l=945 so:-135+945=1080

Lucy sold 945 iPads and Ayu sold 135 iPads

What is an equation?

"It is a mathematical statement which consists of equal symbol between two algebraic expressions."

For given question,

Let Lucy and Ayu sold 'x' and 'y' iPads respectively.

Lucy and Ayu sold a total of 1,080 iPads.

So, we get an equation,

⇒ x + y = 1080           ...............(i)

Lucy sold 7 times as many as Ayu.

So we get the second equation as,

⇒ x = 7y                     ................(ii)

Substitute above value of x in equation (i)

⇒ x + y = 1080

⇒ 7y + y = 1080

⇒ 8y = 1080

⇒ y = 135

This means, Ayu sold 135 iPads

Substitute above value of y in equation (ii)

⇒ x = 7(135)    

⇒ x = 7 × 135

⇒ x = 945

This means, Lucy sold 945 iPads.

Therefore, Lucy sold 945 iPads and Ayu sold 135 iPads

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The mean monthly water bill for 44 residents of the local apartment complex is $104. What is the best point estimate for the mean monthly water bill for all residents of the local apartment complex?

Answers

Answer:

$104

Step-by-step explanation:

The computation of the best point estimate for the mean monthly water bill is shown below:

Given that

The mean monthly water bill is $104

and, the number of residents is 44

based on the above information

The best point estimate would be equivalent to the mean monthly water bill i.e. $104

hence, the same would be considered

the measures of the angles of a triangle are shown in the figure below. solve for x ​

Answers

Answer:

Brainliest????

Step-by-step explanation:

X=23°

The diameter of a circle is 3 meters. What is the circumference?

Answers

Answer:

C≈9.42m

Using any of this formulas

C=2πr

C=2πrd=2r

Solution:

C=πd=π·3≈9.42478m

i need help ////////

Answers

Answer:

[tex]1\frac{1}{2}[/tex] miles = 7920 feet

2[tex]\frac{1}{2}[/tex] miles = 13200 feet

3[tex]\frac{1}{2}[/tex] miles = 18480 feet

4[tex]\frac{1}{2}[/tex] miles = 23760 feet

5[tex]\frac{1}{2}[/tex] miles = 29040 feet

6[tex]\frac{1}{2}[/tex] miles = 34320 feet

Explanation:

1 mile = 5280 feet

[tex]\frac{1}{2}[/tex] miles = 2640 feet

to convert miles into feet, multiply the whole numbers by 5280 and add 2640 to find your overall feet

2[tex]\frac{1}{2}[/tex] : 2 x 5280 + 2640 = 13200 ft

3[tex]\frac{1}{2}[/tex] : 3 x 5280 + 2640 = 18480 ft

4[tex]\frac{1}{2}[/tex] : 4 x 5280 + 2640 = 23760 ft

5[tex]\frac{1}{2}[/tex] : 5 x 5280 + 2640 = 29040 ft

6[tex]\frac{1}{2}[/tex] : 6 x 5280 + 2640 = 34320 ft

HELP PLEASE BRAINLYIST
Examine the diagram. It is not drawn to scale.
Wh at is the m angle 3?
Х
m angle 3=

Answers

Answer:

isn't it just 50°

Step-by-step explanation:

180=a straight line.

you are given 75° and 55°

75+55=130

180-130

Answer:

105

Step-by-step explanation:

Chupapi

Some loser deleted my answers

That's why it says 1 answer and 1.5k people helped

Noah has $5.
1.
a.
Elena has 40% as much as Noah. How much does Elena have?
b.
Compare Elena's and Noah's money using fractions. Draw a diagram to
illustrate.

Answers

Answer:

a. $4

b. Noah has 5/5. Elena has 4/5.

Step-by-step explanation:

Noah has $5.

a.

Elena has 80% of Noah's money.

80% of $5 = 0.80 * $5 = $4

b.

Noah has $5. We can consider $5 to be the full amount.

A full amount is 100% or 1 or 5/5.

Elena has 80% of Noah's money, so she has 80/100 of Noah's money.

80/100 reduces to 4/5.

Noah has 5/5, and Elena has 4/5.

The money that Elena has is $2.

What is percentage?

A percentage is a value that indicates 100th part of any quantity.

A percentage can be converted into a fraction or a decimal by dividing it by 100.

The given problem can be solved as follows,

(a) The amount of money Elena has is 40% of that of Noah.

It can be written as follows,

40% × 5

= 40/100 × 5

= 2

(b) Since the Elena has 40% of the Noah's money,

In the form of fraction it can be written as follows,

40% = 40/100

        = 2/5

This can be represented in a diagram as follows,

In the diagram shown the circle has in total 5 sectors of which 2 yellow sectors represent Elena's money.

Hence, the amount of money Elena has is $2 which is shown in the diagram.

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Find the value of 5⁰ X 7⁰ X 3⁰

plz help asap​

Answers

Answer:

5⁰ × 7⁰ × 3⁰ = 1

Step-by-step explanation:

5⁰ × 7⁰ × 3⁰ = ?

5⁰ = 1

7⁰ = 1

3⁰ = 1

1 × 1 × 1 = 1

Richard has just been given an l0-question multiple-choice quiz in his history class. Each question has five answers, of which only one is correct, Since Richard has not attended a class recently, he doesn't know any of the answers, Assuming that Richard guesses on all 10 questions. Find the indicated probabilities.
A) What is the probability that he will answer all questions correctly?
B) What is the probability that he will answer all questions incorrectly?
C) What is the probability that he will answer at least one of the questions correctly?
Then use the fact that P(r1) = 1 P(r = 0).
D) What is the probability that Richard will answer at least half the questions correctly?

Answers

Answer:

a) 0.0000001024 probability that he will answer all questions correctly.

b) 0.1074 = 10.74% probability that he will answer all questions incorrectly

c) 0.8926 = 89.26% probability that he will answer at least one of the questions correctly.

d) 0.0328 = 3.28% probability that Richard will answer at least half the questions correctly

Step-by-step explanation:

For each question, there are only two possible outcomes. Either he answers it correctly, or he does not. The probability of answering a question correctly is independent of any other question. This means that we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

In which [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]

And p is the probability of X happening.

Each question has five answers, of which only one is correct

This means that the probability of correctly answering a question guessing is [tex]p = \frac{1}{5} = 0.2[/tex]

10 questions.

This means that [tex]n = 10[/tex]

A) What is the probability that he will answer all questions correctly?

This is [tex]P(X = 10)[/tex]

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 10) = C_{10,10}.(0.2)^{10}.(0.8)^{0} = 0.0000001024[/tex]

0.0000001024 probability that he will answer all questions correctly.

B) What is the probability that he will answer all questions incorrectly?

None correctly, so [tex]P(X = 0)[/tex]

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 0) = C_{10,0}.(0.2)^{0}.(0.8)^{10} = 0.1074[/tex]

0.1074 = 10.74% probability that he will answer all questions incorrectly

C) What is the probability that he will answer at least one of the questions correctly?

This is

[tex]P(X \geq 1) = 1 - P(X = 0)[/tex]

Since [tex]P(X = 0) = 0.1074[/tex], from item b.

[tex]P(X \geq 1) = 1 - 0.1074 = 0.8926[/tex]

0.8926 = 89.26% probability that he will answer at least one of the questions correctly.

D) What is the probability that Richard will answer at least half the questions correctly?

This is

[tex]P(X \geq 5) = P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8) + P(X = 9) + P(X = 10)[/tex]

In which

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 5) = C_{10,5}.(0.2)^{5}.(0.8)^{5} = 0.0264[/tex]

[tex]P(X = 6) = C_{10,6}.(0.2)^{6}.(0.8)^{4} = 0.0055[/tex]

[tex]P(X = 7) = C_{10,7}.(0.2)^{7}.(0.8)^{3} = 0.0008[/tex]

[tex]P(X = 8) = C_{10,8}.(0.2)^{8}.(0.8)^{2} = 0.0001[/tex]

[tex]P(X = 9) = C_{10,9}.(0.2)^{9}.(0.8)^{1} \approx 0[/tex]

[tex]P(X = 10) = C_{10,10}.(0.2)^{10}.(0.8)^{0} \approx 0[/tex]

So

[tex]P(X \geq 5) = P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8) + P(X = 9) + P(X = 10) = 0.0264 + 0.0055 + 0.0008 + 0.0001 + 0 + 0 = 0.0328[/tex]

0.0328 = 3.28% probability that Richard will answer at least half the questions correctly

An electrician charges a service fee of $60 to inspect a home. If he has to
work on something he charges $25 per hour. If he charges $172.50, how
many hours did he work?

Answers

Answer:

About 4.5 hours, you can say 5 hours

Step-by-step explanation

You can solve this by constructing a linear equation, which would turn out like this, 25x+60=172.50. How I got this is that it says his charge is 25 per hour, that is basically multiplication by an unknown number, so put that as a variable. Next it says he has a service fee of 60 dollars, this is what's called an initial fee. Now all we need to do is solve for x, which turns into 4.5. I don't know if they ask to round your answer or something, I hope this is right.

The distance around the outside of an apartment is 0.3 mile. Keira ran 0.1 of the distance during her lunch. How far did she run?

Answers

Answer:

0.1

Step-by-step explanation:

00:00

The city council in Middlefield wants to know if residents are in favor of a traffic camera at the main intersection in town. Drag tiles to match each

term to the example it best describes. Each tile may be used only once.

Representative Sample

Population

NOT a Representative Sample

Term

Example

Drivers who reside in Middlefield

Residents of Middlefield

Residents randomly chosen from the town register

Answers

Answer:

Matching Tiles with Terms:

Term                                                Example                                    

NOT a Representative Sample      Drivers who reside in Middlefield

Population                                       Residents of Middlefield            

Representative Sample                  Residents randomly chosen from the

                                                        town register

Step-by-step explanation:

Population includes all the residents of Middlefield.

Representative Sample is a population subset that accurately reflects the characteristics of the population.  For example, the subset of residents who are randomly chosen from the town register is an unbiased and representative sample.

NOT a Representative Sample: For example, drivers who reside in Middlefield do not represent the characteristics of the population of Middlefield.

28.
Car A and car B are 120 km apart. If they move towards each other, they will meet in 1 hour. If they
move in the same direction, car A will catch up with car B in 5 hours. Find the speed of car A and
the speed of car B. (Assume that the speeds of the cars are constant.)​

Answers

let their speeds be x & y
Towards each other effective speed = x+y
t= d/r
120/(x+y) = 1
x+y=120..........................(1)
in the same direction effective speed = x-y
120/(x-y) =5
x-y = 24...................(2)
solve (1) & (2)
add
2x=144
x=72
you find out y

can somebody help me solve for x.

Answers

Answer:

8/3

Step-by-step explanation:

x : 4 = 4 :  6

x = 16/ 6

x = 8/3

It costs $6 per hour for a park to water the grass. How much will it cost to water the grass for
7/3
hours?

Answers

$43.8, do 7.3 (if that’s how long it was) times $6, giving you 43.8

Answer:

I think the answer is $14 hope this helps!

Step-by-step explanation:

A cone in the diagram below has a radius (r) of 10mm and its height (h) is 24mm calculate the length of the slant height

Answers

Answer:

26mm

Step-by-step explanation:

by the Pythagorean theorem,

[tex]x^2=10^2+24^2\\x^2=676\\x=26[/tex]

On Saturday, Ahmed walks his dog 0.5 mile. On the same day, Latisha walks her dog 0.7 times as far as
Ahmed walks his dog.
How far does Latisha walk her dog on Saturday?
Latisha walks her dog mile(s) on Saturday. I have it due by tomorrow at 7 am please help, don’t put the links!!

Answers

0.35?? Latisha walks her dog 0.35 miles on Saturday.

Help please!!!!!! I don't have a lot of time

Answers

Answer:

Its 5,...................

Answer:

5

Step-by-step explanation:

simplify the exponent

35/8-1

simplify

35/7

simplify

5

Write the quadratic equation in standard form.
- 4(x - x²) = 8
Determine if the quadratic function

Answers

Answer:

x² - x - 2 = 0

Step-by-step explanation:

Given:

- 4(x - x²) = 8

Find:

Standards form

Computation:

- 4(x - x²) = 8

(x - x²) = -2

x - x² = -2

x² - x - 2 = 0

In ΔVWX, x = 9.1 inches, w = 5.4 inches and ∠W=161°. Find all possible values of ∠X, to the nearest 10th of a degree

Answers

Answer:

NO POSSIBLE TRIANGLES

Step-by-step explanation:

Answer:

no possible triangles

Step-by-step explanation:

The length of stay at a specific emergency department in Phoenix, Arizona, in 2009 had a mean of 4.6 hours with a standard deviation of 2.9. Assume that the length of stay is normally distributed.
a. What is the probability of a length of stay greater than 10 hours?
b. What length of stay is exceeded by 25% of the visits?
c. From the normally distributed model, what is the probability of a length of stay less than 0 hours? Comment on the normally distributed assumption in this example.

Answers

Answer:

a) the probability of a length of stay greater than 10 hours is 0.03144

b) the length of stay is exceeded by 25% of the visits is 6.5 hrs

c)

P( X < 0 ) = 0.0559

The probability of length of stay less than 0 hours is 0.0559, length of stay cannot be less than 0. When the normal model is used, we assume that the LOF is approximately normally distributed.

The LOF is better modeled by the normal distribution near the mean and worse in the tails.

The probabilities in the left tail for the vales of X < 0  can be neglected.

Step-by-step explanation:

Given that;

mean μ = 4.6

standard deviation σ = 2.9

let x represent length of stay;

a. What is the probability of a length of stay greater than 10 hours?

p( x > 10 ) = p( x-μ/σ > 10-4.6 / 2.9 )

= p( Z > 1.86)

= P( Z < - 1.86 )

FROM THE Z SCORE TABLE;( Z < - 1.86 ) = 0.03144

p( x > 10 )  = 0.03144

Therefore, the probability of a length of stay greater than 10 hours is 0.03144

b) What length of stay is exceeded by 25% of the visits?

p( X > x ) = 0.25

so

p( X < x ) = 0.75

p( x-μ/σ < x-4.6 / 2.9 ) = 75

p( Z < x-4.6 / 2.9 ) = 0.75 ----- 1

also, from the standard normal table; P( Z < 0.67 ) = 0.75 ------ 11

from equation 1 and 11

x-4.6 / 2.9 = 0.67

x-4.6 = 2.9 × 0.67

x - 4.6 = 1.943

x = 4.6 + 1.943

x = 6.543 ≈ 6.5

Therefore, the length of stay is exceeded by 25% of the visits is 6.5 hrs

c)  From the normally distributed model, what is the probability of a length of stay less than 0 hours?

P( X < 0 ) = p( x-μ/σ < 0-4.6 / 2.9 )

= P( Z - 1.59)

from table;( Z - 1.59) = 0.0559

P( X < 0 ) = 0.0559

The probability of length of stay less than 0 hours is 0.0559, length of stay cannot be less than 0. When the normal model is used, we assume that the LOF is approximately normally distributed.

The LOF is better modeled by the normal distribution near the mean and worse in the tails.

The probabilities in the left tail for the vales of X < 0  can be neglected.  


What is the value of the expression below when x=7?
6x+ 10
A. 52
B. 67
C. 42
D.77

Answers

Answer:

52

Step-by-step explanation:

when a letter is next to a number like that and they tell u what the letter is u times it so 6x7+10=52 hope this helped :P

Please answer this :/

Answers

Answer:

-60

Step-by-step explanation:

-45+s=-105

s=-105+45

s=-60

if the circumference of a circle is 52 cm, what is the radius? round to the nearest tenth. PLESE HELP I DONT HAVE THAT MUCH TIME :(

Answers

Answer:

8.3

Step-by-step explanation:

Given,

Circumference of the circle = 52 cm

Therefore ,

By the problem,

[tex] = > 2\pi r = 52[/tex]

[tex] = > 2 \times 3.14 \times r = 52[/tex]

[tex] = > r = \frac{52}{3.14 \times 2} [/tex]

=> r = 8.2802547771

Rounded to nearest tenth,

=> r = 8.3 (Ans)

Suppose that a committee is studying whether there is waste of time in our judicial system. It is interested in the mean amount of time individuals waste at the courthouse waiting to be called for jury duty. The committee randomly surveyed 81 people who recently served as jurors. The sample mean wait time was eight hours with a sample standard deviation of four hours. Construct a 95% confidence interval for the population mean time wasted. Which distribution should you use for this problem

Answers

Answer:

The t-distribution is used, as we have the standard deviation of the sample.

The 95% confidence interval for the population mean time wasted is between 7.12 hours and 8.88 hours.

Step-by-step explanation:

We have the standard deviation for the sample, which meas that the t-distribution should be 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 = 81 - 1 = 80

95% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 80 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 1.99

The margin of error is:

[tex]M = T\frac{s}{\sqrt{n}} = 1.99\frac{4}{\sqrt{81}} = 0.88[/tex]

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

The lower end of the interval is the sample mean subtracted by M. So it is 8 - 0.88 = 7.12 hours.

The upper end of the interval is the sample mean added to M. So it is 8 + 0.88 = 8.88 hours.

The 95% confidence interval for the population mean time wasted is between 7.12 hours and 8.88 hours.

Which would be a good estimate for the tax on $97.95 if the tax is 9.5%?



$12

$10.50

$10

$8.50​

Answers

It would be $10 Sorry if i’m wrong
I believe the answer is $10!!

a normal distribution has a mean of 56 and a standard deviation of 8. Find the percentage of data values that are in the given interval. Use the curve to aid you.​

Answers

Answer:

12) Between 40 and 64 = 0.815

13) Between 32 and 40 = 0.0235

14) Between 56 and 64 = 0.34

15) At most 56 = 0.515

16) At least 72 = 0.025

17) At most 64 = 0.855

Explanation:

To answer this, we will convert each of the values into their standardized form to make this easier.

The standardized score for any value is the value minus the mean then divided by the standard deviation.

z = (x - μ)/σ

x = Each value

μ = Mean = 56

σ = Standard deviation = 8

12) Between 40 and 64

For 40,

z = (x - μ)/σ = (40 - 56)/8 = (-16/8) = -2

For 64

z = (x - μ)/σ = (64 - 56)/8 = (8/8) = 1

So,

Between 40 and 64 = Between -2 and 1

From the curve, noting that the central point is the mean, with standard score of 0, the lines before it move in step of 1 standard deviation towards the negative side, that is, -1, -2, etc. And the lines before the central point move towards the positive side, that is, 1, 2, 3, etc.

So,

Between -2 and 1 = 0.135 + 0.34 + 0.34 = 0.815

13) Between 32 and 40

For 32,

z = (x - μ)/σ = (32 - 56)/8 = (-24/8) = -3

For 40,

z = (x - μ)/σ = (40 - 56)/8 = (-16/8) = -2

So,

Between 32 and 40 = Between -3 and -2 = 0.0235

14) Between 56 and 64

For 56,

z = (x - μ)/σ = (56 - 56)/8 = (0/8) = 0

For 64,

z = (x - μ)/σ = (64 - 56)/8 = (8/8) = 1

Between 56 and 64 = Between 0 and 1 = 0.34

15) At most 56

For 56,

z = (x - μ)/σ = (56 - 56)/8 = (0/8) = 0

At most 56 = At most 0 = 0.0015 + 0.0235 + 0.15 + 0.34 = 0.515

All the regions before z = 0)

16) At least 72

For 72,

z = (x - μ)/σ = (72 - 56)/8 = (16/8) = 2

At least 72 = At least 2 = 0.0235 + 0.0015 = 0.025

(All the regions from z = 2 to the end)

17) At most 64

For 64,

z = (x - μ)/σ = (64 - 56)/8 = (8/8) = 1

At most 64 = At most 1 = 0.0015 + 0.0235 + 0.15 + 0.34 + 0.34 = 0.855

(All the regions before z = 1)

Hope this Helps!!!

A farmer knows that a grocery store will reject a shipment of his vegetables if more than 4% of the vegetables contain blemishes. He inspects a large truckload of tomatoes to determine if the proportion with blemishes (p) exceeds 0.04. He selects an SRS of 150 tomatoes from the more than 2,000 tomatoes in the truck. Suppose that 8 tomatoes sampled are found to have blemishes. Which of the assumptions for inference about a proportion is violated, if any?

a. Large Counts: np > 10
b. Large Counts: n(1 – p) > 10
c. The sample is a random sample of the entire population.
d. 10% condition: the sample size is less than 10% of the population.
e. There do not appear to be any violations.

Answers

Answer:

Assumption A is violated

Step-by-step explanation:

x = number of blemishes = 8

n = sample size = 150

proportion = x/n = 8/150 = 0.0533

1. large counts: np> 10

= 150 * 0.0533 >10

= 7.995 > 10

this assumpton is obviously violated. 7.995 is not greater than 10

2. Large Counts: n(1 - p) > 10

150(1-0.0533)>10

150-7.995 > 10

142.005> 10

there is no violation. The assumption is satisfied

3. This assumption is satisfied. this is because the tomatoes were selected using simple random sampling.

4. 10% of the population = 0.1 * 2000 = 200

the sample size = 150

150 < 200

this assumption is satisfied

Simplify the expression m 4/5x m1/10

Answers

Answer:

√x4

Step-by-step explanation:

(x^2+x−3)⋅(x^2−4)

(y^2+6y+8)−(y^2+y−12)

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