When 4(9y − 5) = 10(3y + 17) − 40 is solved, the result is:
A=20.
B=25.
C=-10.
D=10.

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:

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%

Answer:

0.0783

Step-by-step explanation:

The probability of getting the first success on xtg trial ; this is a geometric distribution :

P(x) = p(1−p)^x−1

The probability of being a universal donor , p = 0.15

The probability of obtaining someone who is a universal donor on 5th trial will be :

P(5) = 0.15(1 - 0.15)^(5 - 1)

P(5) = 0.15(0.85)^4

P(5) = 0.15(0.52200625)

P(5) = 0.0783009375

P(5) = 0.0783

Answer:

0.25

Step-by-step explanation:

Given that :

Mean score, μ = 69

Standard deviation, σ = 4

Score, x = 64

The standardized score, Zscore can be obtained using the formular :

Zscore = (x - μ) / σ

Zscore = (69 - 68) / 4

Zscore = 1 / 4

Zscore = 0.25

Answer:

volume=length×width×height

v=15×20×20

v=6000

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:

volume of prism is 160 cm

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:

Mathematics is very important in a small business is because when you make money transactions with other people you need to know how to count money correctly and your calculations can’t be wrong. When we sign up for jobs like police, or firefighter, we need to use math. Math helps us solve real-world problems.

Step-by-step explanation:

Answer:

Step-by-step explanation:

The angles are x, y and z:

Their sum is:

Then find the other angles:

Now we have to,

find the three angles if one angle is twice smallest angle and third angle is 36° greater than smallest angle.

Then take the values as,

→ smallest angle = x

→ y = 2x

→ z = x + 36°

Let we find the angles,

→ x + y + z = 180°

→ x + 2x + x + 36° = 180°

→ 4x = 180 - 36

→ 4x = 144

→ x = 144/4

→ [x = 36°]

Now the value of y is,

→ y = 2x

→ y = 2 × 36°

→ [y = 72°]

Then the value of z is,

→ z = x + 36°

→ z = 36° + 36°

→ [z = 72°]

Placing values from least to greatest,

→ 36°, 72°, 72°

Hence, the order is 36°, 72°, 72°.

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.

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:

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:

[tex]f(x) = \frac{5}{x}[/tex]

[tex]g(x) = x - 4[/tex]

Step-by-step explanation:

Composite function:

[tex]h(x) = f(g(x)) = (f \circ g)(x)[/tex]

h(x) = 5/x-4

We have x on the denominator and not the numerator, so the outer function is given by:

[tex]f(x) = \frac{5}{x}[/tex]

The denominator is x - 4, so this is the inner function, so:

[tex]g(x) = x - 4[/tex]

Answer:

If rounded to the nearest 10 bacteria, then it would be 500 bacteria.

Step-by-step explanation:

First multiply 150 by two in order to get 300, that leaves 4 hours to figure out. From there you can figure out the rest by seeing that 4 is 2/3 of 6. I converted it into the decimal number .66. Multiply 300 by .66 to get 198 and then add it to 300 to get 498. Then just round it up to the nearest 10 bacteria which leaves you with the final answer of 500 bacteria.

Answer:

Step-by-step explanation:

There are 2 different ways to do this: calculus and by completing the square. In this particular instance, calculus is WAY easier, and since I don't know for what class you are doing this, I'll do both ways. First the calculus way. We know the position equation, and the first derivative of the position is velocity. We also know that when the velocity is equal to 0 is when the object is at its max height. So we'll find the derivative first, then solve it for t:

If [tex]s(t)=-3t^2+20t+2[/tex] then the first derivative is

v(t) = -6t + 20 Solving for t requires that we set the velocity equal to 0 (again, this is where the object is at its max height), so

0 = -6t + 20 and

-20 = -6t so

t = 3.3 seconds. Now that we know that at 3.3 seconds the object is at its highest point, we sub that time into the position function to see where it is at that time:

s(3.3) = [tex]-3(3.3)^2+20(3.3)+2[/tex] and

s(3.3) = 35.3 meters.

Now onto the more difficult way...completing the square. Begin by setting the position function equal to 0 and then move over the constant to get:

[tex]-3t^2+20t=-2[/tex] Since the leading coefficient is not a 1 (it's a 3), we have to factor out the 3, leaving us with:

[tex]-3(t^2-\frac{20}{3}t)=-2[/tex] Now the rule is to take half the linear term, square it, and add it to both sides. Our linear term is [tex]\frac{20}{3}[/tex] and half of that is [tex]\frac{20}{6}[/tex]. Squaring that:

[tex](\frac{20}{6})^2=\frac{400}{36}=\frac{100}{9}[/tex]. We will add that in to both sides. On the left it's easy, but on the right we have to take into account that we still have that -3 sitting out front, refusing to be ignored. So we have to multiply it in when we add it to the right. Doing that gives us:

[tex]-3(t^2-\frac{20}{3}t+\frac{100}{9})=-2-\frac{100}{3}[/tex] We will clean this up a bit now. The reason we do this is because on the left we have created a perfect square binomial which will give us the time we are looking for to answer this question. Simplifying the right and at the same time writing the perfect square binomial  gives us:

[tex]-3(t-\frac{20}{6})^2=-\frac{106}{3}[/tex] Now the last step is to move the constant back over and set the quadratic back equal to y:

[tex]y=-3(t-\frac{20}{6})^2+\frac{106}{3}[/tex].  The vertex of this quadratic is

[tex](\frac{20}{6},\frac{106}{3})[/tex] where

[tex]\frac{20}{6}=3.3[/tex] as the time it takes for the ball to reach its max height of

[tex]\frac{106}{3}=35.3[/tex] meters.

I'd say if you plan on taking calculus cuz you're not there yet, you'll see that many of these types of problems become much simpler when you know it!

Answer:

c is answer

Step-by-step explanation:

yes

Answer:

C

Step-by-step explanation:

took test

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:

128 mph

Step-by-step explanation:

1 hour = 400

4 hours = 240

240+400= 640

4+1 = 5

640/5=128

9514 1404 393

Answer:

  372 m²

Step-by-step explanation:

A vertical line down the center of the figure will divide it into two congruent trapezoids, each with bases 13 and 18, and height 12.

The area of one of them is ...

  A = 1/2(b1 +b2)h

So, the area of the two of them together is ...

  A = (2)(1/2)(b1 +b2)h = (b1 +b2)h

  A = (13 m + 18 m)(12 m) = 372 m²

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:

2/15

Step-by-step explanation:

(-3/5) (-2/9)

Rewriting

-3/9 * -2/5

-1/3 * -2/5

A negative times a negative is a positive.

2/15

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:

B.

Step-by-step explanation:

I don't know for a fact but i think its B. Sorry if I got it wrong.

Answer:

900 at 12%

2100 at 10%

Step-by-step explanation:

Let x= amount invested at 12%

let y= amount invested at 10%

with that being said we can write the two equation

Equation 1: x+y=3000

Equation 2: 3000*.106=.12x+.1y

isolte x from equation 1

x= 3000-y

plug this into equation 2

318=.12(3000-y)+.1y

318=360-.12y+.1y

-42= -.02y

y= 2100

Plug this into equation 1

x+2100=3000

x=900

she should invest $900 into the account earning 12% interest and $2100 into the account earning 10% interest.

Let's denote the amount of money Hattie invests at 12% as \(x\) dollars, and the amount she invests at 10% as \(\$3000 - x\) dollars.

The formula for calculating interest is: \(\text{Interest} = \text{Principal} \times \text{Rate} \times \text{Time}\).

For the 12% account:

Interest_12% = \(x \times 0.12 \times 1\) (1 year)

For the 10% account:

Interest_10% = \((3000 - x) \times 0.10 \times 1\) (1 year)

Hattie wants to earn 10.6% interest on the total investment, so we can set up the equation:

\(\text{Total Interest} = \text{Interest}_12% + \text{Interest}_10%\)

\(3000 \times 0.106 = x \times 0.12 + (3000 - x) \times 0.10\)

Now, solve for \(x\):

\(318 = 0.12x + 300 - 0.10x\)

\(318 = 0.02x + 300\)

\(18 = 0.02x\)

\(x = 900\)

Hattie should invest $900 at 12% and \(3000 - 900 = 2100\) at 10%.

Therefore, she should invest $900 into the account earning 12% interest and $2100 into the account earning 10% interest.

Learn more about interest at https://brainly.com/question/29451175

#SPJ3

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:

Ok so these triangle are the same with equivalent angles

so we can add up the angles 80+26=106

now we subtract from 180

180-106=74

so the measure of angle b is 74

Hope This Helps!!!