6. Construction A total of 18.6 cu yd of concrete is required for pouring a
foundation. The ratio of cement to sand to gravel for this application is
1:2:4, and the total amount of these components must be 1½ times the vol-
ume of concrete needed. Use the method of Example 4 to determine how
many cubic yards of each component are needed.

If the sample of bacteria is growing at an hourly rate of 15% continuously and the  bacteria began with 11 bacteria then there will be 244.178 samples bacteria after 21 hours.

Given growth of bacteria 15% ,bacteria at beginning 11.

We have to find the number of sample of bacteria after 21 hours.

We have to first form exponential function which shows the growth of bacteria in variable t.

Exponential function which shows the sum is y=P[tex]e^{rt}[/tex]

where P is initial amount ,

r is rate and

y is the sum

So in our problem P=11 and r=0.15

y=11*[tex]e^{0.15t}[/tex]

To find the  samples after 21 hours we have to put t=21.

y=11[tex]e^{0.15*21}[/tex]

y=11*[tex]e^{3.1}[/tex]

y=11*22.198  ([tex]e^{3.1}[/tex]=22.198 from e table)

y=244.178

Hence the samples after 21 hours will be 244 approximately.

Learn more about function at https://brainly.com/question/10439235

#SPJ4

According to the order of operations, brackets are solved first which contains the division operation. Hence, 12 is divided by -6 first.  

Order of Operations

Given expression is,

(12 ÷ (-6))(3) + (-2)

According to the BODMAS rule of operations, the precedence order of operations is as follows,

Brackets > Of > Division > Multiplication > Addition > Subtraction

Hence, we will start by solving the brackets first, then solve the division and then the addition.

Evaluation

Solving the given expression as per the order of operations,

Brackets are solved first, then division followed by multiplication and then addition. Division is always of the highest precedence among all operations after brackets and of.

12 ÷ (-6)(3) + (-2)

= 12 ÷ (-6)(3) - 2   [∵ +(-n) = -n]

= (-2)(3) -2

= -6 - 2

= -8

Thus, solving the +(-2) and then division of 12 by (-6) are the first operations to be performed in order to evaluate the given expression.

Learn more about operations here:

https://brainly.com/question/9559872

#SPJ4

Answer:

14.5 hours to the nearest tenth.

Step-by-step explanation:

4.9% = 0.049.

If the original number is 50 it will double to 100 so

100 = 50(1.049)^t

1.049^t = 2

t * log 1.049 = log 2

t = log 2 / log 1.049

 = 14.49 hours,

Answer:

can you give the question?

Step-by-step explanation:

didnt ask a question

the answer of this question is 38 and i hope it s  correct

Answer:

C) -9

Step-by-step explanation:

x + 19 must be half x + 29 because triangles RBC and RST are similar by SAS and RB is half of RS and RC is half of RT.

2(x + 19) = x + 29

2x + 38 = x + 29

x + 38 = 29

x = -9

Answer: 3/7

Step-by-step explanation:

More likely -You are more likely to commit a Type I error

According to statement

we have to find the type 1 error by using the significant levels.

we are commit a MORE LIKELY to find the error by rejecting a true null hypothesis using the 0.05 level of significance than using the 0.01 level of significance.

So, More likely -You are more likely to commit a Type I error

Learn more about HYPOTHESIS here https://brainly.com/question/11555274

#SPJ4

Answer:

Yes.

Step-by-step explanation:

Yes, the given line can be used to make reasonable predictions of the number of cheese pizzas that will be sold, since the scatter points clearly show a trend.

As time goes on, the number of pizzas sold is getting bigger, and the trend is what created the line.

The data was taken over 8 consecutive weeks, so we can assume that it can be used in our prediction.

Since the trend has been pretty consistent over periods of time, we can expect it to continue in the upcoming weeks.

Answer: [tex]42x^3 y^2[/tex]

Step-by-step explanation:

[tex]A=(3xy)(14x^2 y)=42x^3 y^2[/tex]

Answer:

Step-by-step explanation:

To check this, we need to know whether

2

1

​

=

3

2

​

We have,  

2

1

​

=

2×3

1×3

​

=

6

3

​

and  

3

2

​

=

3×2

2×2

​

=

6

4

​

We find that

6

3

​

<

6

4

​

, which means that  

2

1

​

<

3

2

​

.

Therefore, The ratio 1:2 is not equivalent to the ratio 2:3

Answer:

No, they aren't equal.

Step-by-step explanation:

Answer:

[tex]x=-3[/tex]

Step-by-step explanation:

Given equation:

[tex]\dfrac{2x}{x+1}+\dfrac{3(x+1)}{x}=5[/tex]

Make the denominators the same:

[tex]\implies \dfrac{2x}{x+1} \cdot\dfrac{x}{x}+\dfrac{3(x+1)}{x} \cdot \dfrac{x+1}{x+1}=5[/tex]

[tex]\implies \dfrac{2x^2}{x(x+1)}+\dfrac{3(x+1)^2}{x(x+1)} =5[/tex]

Combine the fractions:

[tex]\implies \dfrac{2x^2+3(x+1)^2}{x(x+1)} =5[/tex]

Multiply both sides by x(x+1):

[tex]\implies 2x^2+3(x+1)^2 =5x(x+1)[/tex]

Expand the brackets:

[tex]\implies 2x^2+3(x^2+2x+1) =5x^2+5x[/tex]

[tex]\implies 2x^2+3x^2+6x+3 =5x^2+5x[/tex]

Combine like terms:

[tex]\implies 5x^2+6x+3=5x^2+5x[/tex]

Subtract 5x² from both sides:

[tex]\implies 6x+3=5x[/tex]

Subtract 5x from both sides:

[tex]\implies x+3=0[/tex]

Subtract 3 from both sides:

[tex]\implies x=-3[/tex]

Learn more about algebraic fractions here:

https://brainly.com/question/27943438

https://brainly.com/question/27979364

Answer:

Step-by-step explanation:

Solution

The length of all the rectangles is 7

You need the width to be               4

Area rectangle = L*w

Area rectangle = 7*4

Area rectangle = 28

Answer: B

The radius of the cone's base in the unit is 9*7x².

Given:

To find:

Solution:

As we know, the volume of the cone formula is

V = πr²h/3

So, lets us compare the above formula with the given expression;

πr²h/3 = 3*7x³

Here, h is represented as x, we get;

πr²x/3 = 3*7x³

πr²/3 = 3*7x²

r²= 9*7x²

Hence, the radius of the cone's base, in units, is 9*7x².

To learn more about volume, refer to:

https://brainly.com/question/3390425

#SPJ9

The commutative property of multiplication addition is illustrated below.

The commutative property implies that the changing of orders of the numbers doesn't have a effect on the value.

In this case, 5 × 4 = 20. Also, changing them to 4 × 5 is still 20.

Likewise 2 + 5 as 5 + 2 gives 7.

Learn more about multiplication on:

brainly.com/question/10873737

#SPJ1

By assuming that 1 + 1 = 3, we will reach an absurd.

To do this, we need to reach an absurd.

Let's assume that we are working with integer numbers, and let's assume that 1 + 1 is equal to 3.

Then we can write:

1 + 1 = 3

Now, if we subtract 1 in both sides, we get:

(1 + 1) - 1 = 3 - 1

1  = 2

Now we can subtract 1 again so we get:

1 - 1 = 2 - 1

0 = 1

This is an absurd, then the statement:

1 + 1 = 3

is false.

So we conclude that:

1 + 1 isn't 3.

If you want to learn more about math statements:

https://brainly.com/question/1885950

#SPJ1

Answer:

1/7

Step-by-step explanation:

When 2 lines are perpendicular the gradient of one is the reciprocal of the other :

If the gradient of A was 2 the gradient of B would be 1/2.

If the gradient of a is 7 the gradient of b would be 1/7 .

Hope this helped and have a good day

a. The equation we get is 10(1.5 + x) = 80, where x is the number of hours Sheila can afford to hire the babysitter.

b. Sheila can afford the babysitter for 6 hours and 30 minutes.

c. The equation we get is 15(1 + x) = 80, where x is the number of hours Sheila can afford to hire the new babysitter.

d. Sheila can afford to hire the new babysitter for 4 hours and 20 minutes, while the first babysitter was hired for 6 hours and 30 minutes.

Thus, Sheila can't afford the same amount of babysitting from the second sitter as she could from the first sitter.

a. We assume the hours affordable to Sheila be x hours.

Per hour charge of the babysitter = $10.

Time taken by the babysitter traveling = 1.5 hours.

Therefore, total chargeable time = 1.5 + x.

Therefore, the total charge by the babysitter = $10(1.5 + x).

This needs to be equal to the amount Sheila is willing to spend, that is, $80.

Thus, the equation we get is: 10(1.5 + x) = 80.

b. We are asked to determine the hours Sheila can afford to hire the babysitter.

We have got the equation 10(1.5 + x) = 80, where x is the hours Sheila can afford to hire the babysitter.

Thus, by solving this equation, we can determine the hours Sheila can afford to hire the babysitter.

10(1.5 + x) = 80,

or, 1.5 + x = 8,

or, x = 8 - 1.5 = 6.5 = 6 hours and 30 minutes.

Thus, Sheila can afford the babysitter for 6 hours and 30 minutes.

c. Per hour charge of the new babysitter = $15.

Time taken by the new babysitter traveling = 1 hour.

Therefore, total chargeable time = 1 + x.

Therefore, the total charge by the new babysitter = $15(1 + x).

This needs to be equal to the amount Sheila is willing to spend, that is, $80.

Thus, the equation we get is: 15(1 + x) = 80.

d. We are asked whether Sheila affords the same amount of babysitting from the second sitter as she could from the first sitter.

To determine this, we need to find the hours she affords from the second babysitter, for which, we solve the equation 15(1 + x) = 80 as  follows:

15(1 + x) = 80,

or, 1 + x = 80/15,

or, x = 80/15 - 1 = 65/15 = 13/3 = 4 hours and 20 minutes.

Sheila can afford to hire the new babysitter for 4 hours and 20 minutes, while the first babysitter was hired for 6 hours and 30 minutes.

Thus, Sheila can't afford the same amount of babysitting from the second sitter as she could from the first sitter.

Learn more about writing and solving equations at

https://brainly.com/question/24145091

#SPJ4

C) graph of a quadratic function with a minimum at 2.5, negative 2.25 and x intercepts at 1 and 4

Standard Form of a Quadratic Function: ax² + bx + c = 0, where a ≠ 0

Given function: x² - 5x + 4

⇒ a = 1, b = -5, c = 4

The minimum of a function is the lowest point of its parabola. We can use the following formula to find the vertex or the minimum of the function: [tex]x=\dfrac{-b}{2a}[/tex] . This will give us the x-value of the vertex, and we will need to solve for the y-value.

The vertex or minimum.

Step 1: Find the x-value of the vertex.

[tex]\\\implies x=\dfrac{-(-5)}{2(1)}\\\\\implies x=\dfrac{5}{2}=2.5[/tex]

Step 2: Find the y-value of the vertex by substituting 2.5 as the value of x in the given function.

[tex]\\\implies x^2 - 5x + 4\\\\\implies 2.5^2-5(2.5)+4\\\\\implies 6.25-12.5+4\\\\\implies -2.25[/tex]

Vertex: (2.5, -2.25)

The x-intercepts (roots).

We can use the Quadratic Formula to find the roots of this function.

Quadratic Formula: [tex]x=\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex] when [tex]ax^2+bx+c=0[/tex]

Equation: x² - 5x + 4 = 0

⇒ a = 1, b = -5, c = 4

Step 1: Substitute the values of a, b, and c into the formula. 

[tex]\\\implies x=\dfrac{\bold{-(-5)}\pm\sqrt{\bold{(-5)^2}\bold{-4(1)(4)}}}{\bold{2(1)}}\\\\\implies x=\dfrac{5\pm\sqrt{\bold{25-16}}}{2}\\\\\implies x=\dfrac{5\pm\sqrt{\bold{9}}}{2}\\\\\implies x=\dfrac{5\pm3}{2}[/tex]

Step 2: Separate into two possible cases.

[tex]x_1=\dfrac{5-3}{2}\implies \dfrac{2}{2}\implies \boxed{1}\\\\x_2=\dfrac{5+3}{2}\implies \dfrac{8}{2}\implies \boxed{4}[/tex]

The x-intercepts of the given function are 1 and 4.

Learn more about quadratic equations here:

brainly.com/question/28105589

brainly.com/question/27988150

Answer:

n = 100

Step-by-step explanation:

the area (A) of the sector is calculated as

A = area of circle × fraction of circle

given A = 40π , then

πr² × [tex]\frac{n}{360}[/tex] = 40π

π × 12² × [tex]\frac{n}{360}[/tex] = 40π

144π × [tex]\frac{n}{360}[/tex] = 40π ( divide both sides by π )

144 × [tex]\frac{n}{360}[/tex] = 40 ( multiply both sides by 360 to clear the fraction )

144n = 14400 ( divide both sides by 144 )

n = 100

The amplitude, Period, Horizontal Shift and Vertical Shift of both graphs are as detailed below.

3)a. Amplitude is the distance between the center line and the positive or negative peak of the graph. Thus, the amplitude is 0.5.

b. The period is the time it takes for the graph to repeat or complete one cycle and in this graph, it is 3.

c. Looking at the graph, ideally the coordinate (3, -1.5) should have been on the y-axis which is at (0, -1.5). This means it was shifted by 3 units to the right side.

d. The positive peak should be equal to the negative peak but in this case, it is not so and as such the center should be on the x-axis which means that the graph was shifted down vertically by 2 units.

4) a. Amplitude is the distance between the center line and the positive or negative peak of the graph. Thus, the amplitude is 3 - 1 = 2

b. The period is the time it takes for the graph to repeat or complete one cycle and in this graph, it is 6.

c. Looking at the graph, ideally the coordinate (4, -1) should have been on the y-axis which is at (0, -1). This means it was shifted by 4 units to the right side.

d. The positive peak should be equal to the negative peak but in this case, it is not so and as such the center should be on the x-axis which means that the graph was shifted up vertically by 1 unit.

Read more about trigonometric graph features at; https://brainly.com/question/17075439

#SPJ1

Using the binomial distribution, the probabilities are given as follows:

a) 0.4159 = 41.59%.

b) 0.5610 = 56.10%.

c) 0.8549 = 85.49%.

The formula is:

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

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

The parameters are:

For this problem, the values of the parameters are:

n = 3, p = 0.76.

Item a:

The probability is P(X = 2), hence:

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

[tex]P(X = 2) = C_{3,2}.(0.76)^{2}.(0.24)^{1} = 0.4159[/tex]

Item b:

The probability is P(X < 3), hence:

P(X < 3) = 1 - P(X = 3)

In which:

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

[tex]P(X = 3) = C_{3,3}.(0.76)^{3}.(0.24)^{0} = 0.4390[/tex]

Then:

P(X < 3) = 1 - P(X = 3) = 1 - 0.4390 = 0.5610 = 56.10%.

Item c:

The probability is:

[tex]P(X \geq 2) = P(X = 2) + P(X = 3) = 0.4159 + 0.4390 = 0.8549[/tex]

More can be learned about the binomial distribution at https://brainly.com/question/24863377

#SPJ1

Yes

See

3 contractors took 8hours

4 contractors took 6hours

We observe

So it's inverse variation

Answer:

[tex]\fbox {Yes}[/tex]

Step-by-step explanation:

An inverse variation can be seen when two factors are compared, if one factor is seen to be increasing, then naturally the factor should be decreasing.

Here, as the number of contractors increase, the time taken to complete the work decreases.

∴ Hence, this represents an inverse variation.

Rule 1:

1, 3, 7, 15, 31, 63, 127, 255, 511, 1023 etc

Rule 2:

40, 24, 16, 12, 10, 9, 8.5, 8.25, 8.125, 8.0625 etc

Hope this helps!

The value of x from the given expression is 23

Given the following equation

√3x+12 = 9

Square both sides

√3x+12)² = 9²

3x + 12. = 81

Subtract 12 from both sides

3x + 12 - 12 = 81- 12

3x = 69

x = 23

Hence the value of x from the given expression is 23

Learn more on equations here: https://brainly.com/question/2972832

#SPJ1

Triangle ABC is dilated by a scale factor of 5 to get A'(-15, -5), B'(10, -10) and C'(-5, -20)

Transformation is the movement of a point from its initial location to a new location. Types of transformations are reflection, translation, rotation and dilation.

Rigid transformation preserves the shape and size of the figure. Reflection, translation, rotation are rigid transformations.

Triangle ABC has vertices at A(-3, -1), B(2, -2) and C(-1, -4). It is then dilated by a scale factor of 5 to get A'(-15, -5), B'(10, -10) and C'(-5, -20)

Find out more on transformation at: https://brainly.com/question/4289712

#SPJ1

The equation of the line parallel to the line KL passing through the points (-6, 8) and (6, 0), and going through the point M (-4, -2) is 2x + 3y = -6. The point satisfying this equation is (-6, 2). Thus, the 2nd option is the right choice.

Slope of the line KL = (8 - 0)/(-6 - 6) = 8/(-12) = -2/3.

Using the formula of the slope of the line passing through the points (x₂, y₂) and (x₁, y₁), as m = (y₂ - y₁)/(x₂ - x₁).

The slope of the line parallel to the line KL will be equal to the slope of KL.

Thus, the slope of the required line is m = -2/3.

The required line also passes through point M (-4, -2).

Thus, the equation of the required line will be,

y - (-2) = (-2/3)(x - (-4)) {Using the equation of the line passing through the point (x₁, y₁) and a slope m, as y - y₁ = m(x - x₁)},

or, y + 2 = (-2/3)(x + 4),

or, 3(y + 2) = -2x - 8,

or, 2x + 3y = -6.

From the given points, only the point (-6, 2) satisfies the equation.

Thus, the equation of the line parallel to the line KL passing through the points (-6, 8) and (6, 0), and going through the point M (-4, -2) is 2x + 3y = -6. The point satisfying this equation is (-6, 2). Thus, the 2nd option is the right choice.

Learn more about parallel lines at

https://brainly.com/question/13763238

#SPJ4

The provided question is incomplete. The complete question is:

"On a coordinate plane, line K L goes through (negative 6, 8) and (6, 0). Point M is at (negative 4, negative 2). Which point could be on the line that is parallel to line KL and passes through point M?

(–10, 0)

(–6, 2)

(0, –6)

(8, –10)"

Answer:

396 gold bars

Step-by-step explanation:

first of all we will find numbers of gold bar 7*99

which is 693 and

we will find number of silver bars 11*99

which is 1089

then 1089-693=

396

Answer:

These lines are perpendicular.

Step-by-step explanation:

Put both equations in the slope intercept form of a line.

y = -6x - 8  This is already in the slope intercept form for a line

-x + 6y = 12  Add x to both sides of the equation

6y = x + 12  Divide through the whole equation by 6

y = 1/6x +2  

Now we compare the two slopes of -6 and 1/6.  They are negative reciprocals of each other.  That means that the line are perpendicular.