Help me pls I am bad at math

Step-by-step explanation:

x²+12x=40

(x+6)²-6²-40=0

(x+6)²-76 = 0

Answer:

probability[Number of 6 random sample do not have cavities] = 0.8

Step-by-step explanation

Given:

Number of student do not have cavities = 60%

Number of random sample = 9 children

Find:

Probability[Number of 6 random sample do not have cavities]

Computation:

n = 9

p = 60% = 0.6

P(At least 6)  

Probability[Number of 6 random sample do not have cavities] = 1 - P(Less than 6)  

Probability[Number of 6 random sample do not have cavities] = 1 - P(Less than or equal to 6)

Probability[Number of 6 random sample do not have cavities] = 0.8

Answer:

volume of prism is 160 cm

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

Answer:

9.48

Step-by-step explanation:

Answer:

Just Between Friends

The percentage of consignors who receive a check for more than $370 is:

= 16%.

Step-by-step explanation:

Mean of consignor check, μ = $480

Standard deviation, σ = $110

Value of check received, x > $370

Solution: find the z-score to determine the percentage of consignors who receive a check for more than $370:

z = (x-μ)/σ

z= ($370 - $480)/$110

z = -$110/$110

z = -1.00

Percentage of consignors who receive a check for more than $370

= 0.15866

= 0.16

= 16%

Full question:

Every 5 years the Conference Board of the Mathematical Sciences surveys college math departments. In 2000 the board reported that 51% of all undergraduates taking Calculus I were in classes that used graphing calculators and 31% were in classes that used computer assignments. Suppose that 16% used both calculators and computers. a) What percent used neither kind of technology? b) What percent used calculators but not computers? c) What percent of the calculator users had computer assignments? d) Based on this survey, do calculator and computer use appear to be independent events? Explain.

Answer:

a. 34%

b. 35%

c. 31.4%

d. Independent events

Explanation:

a. To calculate percentage that used neither kind of technology, we already know those that use the technologies and total taking calculus so:

100%-51%-31%-16%= 34%

b. Percentage that used calculators but not computers.

= 51%-16%=35%

c. Percentage of the calculator users that had computer assignments?

= 16/51×100=31.4% (there are 16 people using both so that as a percentage of 51 people using calculators)

d. Independent events are events that do not affect the other, such that occurrence of one does not define occurrence of the other. Since percentage of calculator and computer assignment users is close to those who are not using any, we can say they are independent events.

Answer:

Purplemath

Introduces reflections in the x- and y-axes. ... To see how this works, take a look at the graph of h(x) = x2 + 2x – 3. ... The previous reflection was a reflection in the x-axis. ... f (x – b) shifts the function b units to the right.

Answer:

y = 6x + 6

Step-by-step explanation:

so; the y as seen will be constant as well as the x

With change of subject the 5 will be moved to the other side having y= 6x +1 + 5 .Given us y = 6x + 6.

Answer:

The null hypothesis is [tex]H_0: p \leq x[/tex], in which x is the proportion tested.

The alternative hypothesis is [tex]H_1: p > x[/tex]

Step-by-step explanation:

A recent article in a university newspaper claimed that the proportion of students who commute more than miles to school is no more than x.

This means that at the null hypothesis, we test if the proportion is of at most x, that is:

[tex]H_0: p \leq x[/tex]

Suppose that we suspect otherwise and carry out a hypothesis test.

The opposite of at most x is more than x, so the alternative hypothesis is:

[tex]H_1: p > x[/tex]

Answer:

The designed life should be of 21,840 vehicle miles.

Step-by-step explanation:

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Mean of 35,000 vehicle miles and a standard deviation of 7,000 vehicle miles.

This means that [tex]\mu = 35000, \sigma = 7000[/tex]

Find its designed life if a .97 reliability is desired.

The designed life should be the 100 - 97 = 3rd percentile(we want only 3% of the vehicles to fail within this time), which is X when Z has a p-value of 0.03, so X when Z = -1.88.

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]-1.88 = \frac{X - 35000}{7000}[/tex]

[tex]X - 35000 = -1.88*7000[/tex]

[tex]X = 21840[/tex]

The designed life should be of 21,840 vehicle miles.

Answer:

7x = x + 9.

Step-by-step explanation:

7 × something = something + 9, right?

So, 7x = x + 9.

Answer:

10

Step-by-step explanation:

10-7 do it yourself and don't vheat

Answer:

Step-by-step explanation:

                          Statements                                 Reasons

1). CD is an altitude of ΔABC                1). Given

2). ΔACD and ΔBCD are right              2). Definition of right triangles.

    triangles.

3). a² = (c - x)² + h²                                 3). Pythagoras theorem

4). a² = c² + x² - 2cx + h²                       4). Square the binomial.

5). b² = x² + h²                                       5). Pythagoras theorem.

6). cos(x) = [tex]\frac{x}{a}[/tex]                                           6). definition of cosine ratio for an angle

7). bcos(A) = x                                        7). Multiplication property of equality.

8). a² = c² - 2c(bcosA) + b²                    8). Substitution property

9). a² = b² + c² - 2bc(cosA)                    9). Commutative properties of

                                                                    addition and multiplication.

Answer:

The answer is D, the last one.

9514 1404 393

Answer:

  (d)  opens up, (1, -3), narrower

Step-by-step explanation:

The factor of +2 multiplying the function tells you the graph is expanded vertically by a factor of 2. The parent function opens upward, and the positive sign on this expansion factor does not change that. The expansion means that y-values will be farther from the vertex for the same x-value distance from the vertex. This give the appearance of a narrower graph.

As always, the transformation ...

  f(x -h) +k

moves the vertex from (0, 0) to (h, k). Here, you have (h, k) = (1, -3), so that is the location of the vertex of the transformed function.

Answer:

cos(60°) = [tex]\frac{adjacent}{hypotenuse}=\frac{y}{10\sqrt{3} }[/tex]

[tex]cos(60)=\frac{y}{10\sqrt{3} } \\y=cos(60) * 10\sqrt{3} \\y=\frac{1}{2} * 10\sqrt{3}\\y=\frac{10\sqrt{3}}{2} =5\frac{\sqrt{3} }{2} =8.66[/tex]

sin(60°) = [tex]\frac{opposite}{hypotenuse} =\frac{x}{10\sqrt{3} }[/tex]

[tex]sin(60)=\frac{x}{10\sqrt{3} } \\x=sin(60)*10\sqrt{3} \\x=\frac{\sqrt{3} }{2} *10\sqrt{3} \\x=\frac{10(\sqrt{3} ) (\sqrt{3} )}{2} \\x=\frac{10*3}{2} =\frac{30}{2} =15[/tex]

Answer:

One lamp is equal to 23 dollars

One table is equal to 42 dollars.

Step-by-step explanation:

We can solve this by first organizing what we have.

1 table (t) + 2 lamps (l) = 88.

2 tables (t) + 3 lamps (l) = 153.

_____________

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

1t + 2l = 88

2t + 3l = 153

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

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

If we multiply both sides by 2 on the first equation of

1t + 2l = 88

we could get

2t + 4l = 176.

If that is true, we can subtract the second equation of

2t + 3l = 153 from the new equation to get the price of a lamp.

    2t + 4l = 176

-    2t + 3l = 153

____________

= 0t + l = 23

One lamp is equal to 23.

We can check this by plugging it into an equation.

1 + 2(23) = 88

1t + 46 = 88

1t + 46 - 46 = 88 - 46

1t = 42

If one table equals 42, we can put this back into the second equation to check.

2 (42) + 3 (23) = 153

84 + 69 = 153

That is correct.

Another way to solve is to put this like a system of equations in a graph, by replacing "t" by "x" for example, and "l" by y.

Then you could put it into a graphing calculator and solve by looking for the place where the two lines converge or meet.

Since we put "x" for "t", that means that whatever the x-value is on the solution point, that is the cost of a table, and the y-value is the cost of the lamps.

Another way to solve, is to find the unit rate first by subtracting the first equation from the second equation.

    2t + 3l = 153

 -  1t + 2l = 88

____________

= t + l = 65

If t + l = 65, we can rearrange that equation to be something like t = 65 - l.

That means "t" is equal to 65 bucks minus a lamp.

We put this back into the first equation of

1t + 2l = 88

and replace "t" with the previous expression.

1(65 - l) + 2l = 88

Simplify/distributive property

65 - l + 2l = 88

65 - 65 - l + 2l = 88 - 65

-l + 2l = 23

l = 23

One lamp is equal to 23 bucks.

Confirmed :)

A lamp cost $23

Let the cost of a table be represented by x

Let the cost of a lamp be represented by y.

Since one table and two lamps cost $88, this can be represented as:

x + 2y = 88 ........ equation i

Since two tables and three lamps cost $153, this can be represented as:

2x + 3y = 153 ........ equation ii

Therefore, the equations are:

x + 2y = 88 ....... i

2x + 3y = 153 ....... ii

From equation i,

x + 2y = 88

x = 88 - 2y ...... iii

Put the value of x into equation ii

2x + 3y = 153

2(88 - 2y) + 3y = 153

176 - 4y + 3y = 153

Collect like terms

-4y + 3y = 153 - 176

-y = -23

y = 23

Therefore, a lamp cost $23

Read related question on:

https://brainly.com/question/15165519

Answer:

128 mph

Step-by-step explanation:

1 hour = 400

4 hours = 240

240+400= 640

4+1 = 5

640/5=128

Answer:

The 95% confidence interval for the mean level of argon gas present in the facility is (374.4, 401.7).

Step-by-step explanation:

Before building the confidence interval, we have to find the sample mean and the sample standard deviation.

Sample mean:

[tex]\overline{x} = \frac{381.3+394.8+396.1+380}{4} = 388.05[/tex]

Sample standard deviation:

[tex]s = \sqrt{\frac{(381.3-388.05)^2+(394.8-388.05)^2+(396.1-388.05)^2+(380-388.05)^2}{3}} = 8.58[/tex]

Confidence interval:

We have the standard deviation for the sample, so 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 = 4 - 1 = 3

95% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 3 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 3.1824

The margin of error is:

[tex]M = T\frac{s}{\sqrt{n}} = 3.1824\frac{8.58}{\sqrt{4}} = 13.65[/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 388.05 - 13.65 = 374.4

The upper end of the interval is the sample mean added to M. So it is 388.05 + 13.65 = 401.7

The 95% confidence interval for the mean level of argon gas present in the facility is (374.4, 401.7).

The question is incomplete. The complete question is :

The breaking strengths of cables produced by a certain manufacturer have a mean of 1900 pounds, and a standard deviation of 65 pounds. It is claimed that an improvement in the manufacturing process has increased the mean breaking strength. To evaluate this claim, 150 newly manufactured cables are randomly chosen and tested, and their mean breaking strength is found to be 1902 pounds. Assume that the population is normally distributed. Can we support, at the 0.01 level of significance, the claim that the mean breaking strength has increased?

Solution :

Given data :

Mean, μ = 1900

Standard deviation, σ = 65

Sample size, n = 150

Sample mean, [tex]$\overline x$[/tex] = 1902

Level of significance = 0.01

The hypothesis are :

[tex]$H_0 : \mu = 1900$[/tex]

[tex]$H_1 : \mu > 1900$[/tex]

Test statics :

We use the z test as the sample size is large and we know the population standard deviation.

[tex]$z=\frac{\overline x - \mu}{\sigma / \sqrt{n}}$[/tex]

[tex]$z=\frac{1902-1900}{65 / \sqrt{150}}$[/tex]

[tex]$z=\frac{2}{5.30723}$[/tex]

[tex]$z=0.38$[/tex]

Finding the p-value:

P-value = P(Z > z)

             = P(Z > 0.38)

             = 1 - P(Z < 0.38)

From the z table. we get

P(Z < 0.38) = 0.6480

Therefore,

P-value = 1 - P(Z < 0.38)

            = 1 - 0.6480

             = 0.3520

Decision :

If the p value is less than 0.01, then we reject the [tex]H_0[/tex], otherwise we fail to reject  [tex]H_0[/tex].

Since the value of p = 0.3520 > 0.01, the level of significance, then we fail to reject  [tex]H_0[/tex].

Conclusion :

At a significance level of 0.01, we have no sufficient evidence to support that the mean breaking strength has increased.

Answer:

16 years

Step-by-step explanation:

Given that :

Earth's distance from sun = 93 million miles

Number of years to complete an orbit = 1 year

Average orbiting distance of new asteroid = 1488 million miles

Number of years to complete an orbit = x

93,000,000 Miles = 1

1488000000 miles = x

Cross multiply :

93000000x = 1488000000

x = 1488000000 / 93000000

x = 16 years

Period taken to orbit the sun = 16 years

Answer: 64 Earth years...

Answer:

Step-by-step explanation:

they say by noon 4 inches of rain has fallen,    then the say that it's falling at  1/4 inch per hour

f(x) = 1/4x +4

where x is in hours, and  f(x)  represents the linear graph of the amount of rain that has fallen after noon   :)

so by 2:30   or  2.5 hours....  then

f(2.5) = 1/4x +4

y = 1/4 (2.5) +4  ( i moved to the y  b/c now there is an answer)

y =[tex]\frac{5}{8}[/tex] + 4

y =4[tex]\frac{5}{8}[/tex]   inches of rain

Answer:

a) y = 1/4x + 4

b) 4.625 inches

Step-by-step explanation:

a) y(0) = 4 inches

slope = 1/4 rate

y = 1/4x + 4

b) 12:00pm (noon) to 2:30pm = 2 hours 30 mins = 2.5 hours

y = 1/4x + 4

y = (1/4)(2.5) + 4

y = 0.625 + 4

y = 4.625 inches

Dada una ecuación de la forma

Tenemos que:

Sabemos que:

f(x)=1+6Sen(2x+π/3)

Y podemos reescribirla como:

f(x)=6Sen(2(x+π/6))+1

Siendo:

La imagen de una función trigonométrica de esta forma es:

y ∈ [-A+D,A+D]

y ∈ [-6+1, 6+1]

y ∈ [-5,7]

La gráfica se adjunta.

Answer:

3 units

Step-by-step explanation:

(4,2) (7,2)

Subtract 4 from 7 = 3

Subtract 2 from 2 = 0

This means that (7,2) is 3 units up from (4,2).

:) ur welcome

Answer:

Step-by-step explanation:

D=√(x2-x1)²+(y2-y1)²

D=√(7-4)²+(2-2)²

D=√(3)²+0

D=3²*½

D=3

Answer:

A. 40

Step-by-step explanation:

Answer:

A. 40

Step-by-step explanation:

75 ÷ 1.5 = 50 = original number

80% of 50 = 50 × 0.8 = 40

Answer:

53.06°F

Step-by-step explanation:

Given the equation of best fit :

y=-3.32x +97.05.

The average temperature for a month with 13.25 inches of Rainfall

Amount of Rainfall = x

Average temperature = y

To make our prediction ; put x = 13.25 in the equation and solve for y ;

y = -3.32x +97.05

Put x = 13.25

y = -3.32(13.25) +97.05

y = - 43.99 + 97.05

y = 53.06°F