Erin is selling books for $12 each. She wants to make more than $180 in book sales. Write an inequality that can be used to determine the number of books, b, she must sell in order to meet her goal, then solve for b.

(a) The mean of Y is 100 meters, and the standard deviation of W is approximately 0.7348 meters.

(b) The mean of W is 100 meters, and the standard deviation of W is approximately 0.6935 meters.

a) To find the mean and standard deviation of Y, where Y = (X₁ + X₂) / 2, we use the properties of the mean and variance of a sum of independent random variables.

Mean of Y:

The mean of Y is simply the average of the means of X₁ and X₂, as the measurements are independent and have the same true height of 100 meters.

Mean(Y) = (Mean(X₁) + Mean(X₂)) / 2 = (100 + 100) / 2 = 100 meters

The standard deviation of Y:

When adding or subtracting independent random variables, the variances add up. Since the measurements are independent, we can use the formula:

Var(Y) = Var((X₁ + X₂) / 2) = (Var(X₁) + Var(X₂)) / 4

Now, calculate the variance of Y:

Var(Y) = (1.2² + 0.85²) / 4 ≈ 0.54

Standard deviation(Y) = √Var(Y)
                                    ≈ √0.54
                                      ≈ 0.7348 feet

b) Now, let's find the mean and standard deviation of W, where W = (1/3)X₁ + (2/3)X₂.

Mean of W:

Mean(W) = (1/3) * Mean(X₁) + (2/3) * Mean(X₂)
               = (1/3) * 100 + (2/3) * 100
               = 100 meters

The standard deviation of W:

To calculate the standard deviation of W, we need to find the variance of W and then take its square root.

Var(W) = (1/3)² * Var(X₁) + (2/3)² * Var(X₂)
            = (1/9) * 1.2² + (4/9) * 0.85²

Now, calculate the variance of W:

Var(W) = 0.0181 + 0.1956 =0.481

Standard deviation(W) = √Var(W)
                                     ≈ √0.481
                                      ≈ 0.6935 meters

So, the mean of W is 100 meters, and the standard deviation of W is approximately 0.6935 meters.

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Answer:

176cm

Step-by-step explanation:

therefore r=13÷2 =r=7.5. and pieces =22÷7

then we substitute

22÷7×(7.5 ×7.5)

=3.14×56.25

=176.58

to the nearest whole =176cm

There is a dramatic change in desert temperatures from day to night because B. of the lack of water.

It should be noted that because the air in the desert is so dry, heat escapes quickly at night, the temperature can vary dramatically from day to night. The temperature during the day averages 38°C, while at night it can drop to -4°C in some deserts. The temperature varies greatly depending on where you are in the desert.

During the day, the sand's radiation from the sun's energy superheats the air, causing temperatures to rise. And, because the desert air is so dry, heat escapes quickly at night, according to NASA. The desert biomes are the driest of all biomes.

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Answer: $14.18

Step-by-step explanation:

Because total change is the amount the cashier is giving back to us,

we can do

$ amount given - $ price of order = $ total change

So:

50 - 35.82 = $14.18

The cashier will give us $14.18 back in change.

A small change in x can change the conclusion of our test.

Given :

how would your conclusion change if your sample mean had been 1.355 mg/l.

t - test :

A t-test is a statistical test that compares the means of two samples. It is used in hypothesis testing, with a null hypothesis that the difference in group means is zero and an alternate hypothesis that the difference in group means is different from zero.

if x = 1.355

t = 1.355 - 1.3 / 0.18 / [tex]\sqrt{30}[/tex]

= 0.055 / 0.18 / [tex]\sqrt{30}[/tex]

= 0.055 * [tex]\sqrt{30}[/tex] / 0.18

= 1.67

df = n - 1

= 30 - 1

= 29

P - value from t table :

p = 0.525

fail to reject [tex]H_0[/tex]

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Full question :

The Environmental Protection Agency has determined that safe drinking water should contain no more than 1.3 mg/liter of copper. You are testing water from a new source, and take 30 water samples. The mean copper content in your samples is 1.36 mg/l and the standard deviation is 0.18 mg/l. There do not appear to be any outliers in your data .

how would your conclusion change if your sample mean had been 1.355 mg/l? what point does this make about statistical significance?

Answer:

Step-by-step explanation:

It is not a prime factorization because the term 8 is common multiplied by 2 and the line has 2 elevated to 3 that itselt is 8.

A prime factorization should be stay equal without any commom multiples.

Answer: 11.5

Step-by-step explanation:

[tex]\sin 35^{\circ}=\frac{x}{20}\\\\x=20 \sin 35^{\circ}\\\\x=11.5[/tex]

Answer:

Step-by-step explanation:

Only a line that goes from (0, 0) and (3.6, 14.4) satisfy the given relationship.

        y = mx

        m = y/x

        [m] is called constant of proportionality.

Given is a graph as shown in the figure.

The graph represents a proportional relationship. The possible coordinates that can be plotted are (x, y) and not (y, x). Only a line that goes from (0, 0) and (3.6, 14.4) satisfy the given relationship.

Therefore, only a line that goes from (0, 0) and (3.6, 14.4) satisfy the given relationship.

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Answer:

x=36

Step-by-step explanation:

The length of a secant segment and a tangent segment drawn to a circle drawn from an external point is:

whole secant * external secant = tangent^2

(12+x)*12=24^2

144+12x=576

12x=432

x=36

Answer:

3.75mm

Step-by-step explanation:

4.5/3=1.5

1.5(2.5)=3.75

the ratios are the same

Answer:

68 cm^2

Step-by-step explanation:

A = ((a+b)/2) x h

A = ((6+11)/2) x 8

A = 68 cm^2

I hope my answer helps you.

Answer:

Area of the trapezium is 68[tex]cm^{2}[/tex]

Step-by-step explanation:

[tex]Given[/tex],

[tex]Parallel side\\[/tex] [tex]A[/tex]= 6cm

[tex]Parallel[/tex][tex]sideB=11cm[/tex]

[tex]Height = 8[/tex]

Formula to find the area of the trapezium

[tex]Area[/tex] [tex]of[/tex][tex]Trapezium[/tex]=[tex]\frac{1}{2}(a+b)h[/tex]

[tex]\frac{1}{2}[/tex][tex](6+11)8[/tex]

[tex]\frac{1}{2}[/tex] X[tex]136\\[/tex]

[tex]68[/tex]

Hence the area of the trapezium is 68

The inequality that represents all possible combinations of x, the number of monitors, and y, the number of keyboards, the university can buy for the computer lab is 250x + 50y <= 4500

Which inequality represents all possible combinations?

The given parameters are:

Spending = At most $4,500

Cost of monitor (x) = $250 per unit

Cost of keyboard (y) = $50 per unit

The total spending is represented as

Total = 250 * x + 50 * y

This gives

Total = 250x + 50y

The spending is at most $4,500 i.e less than or equal to

So, we have

250x + 50y <= 4500

Hence, the inequality that represents all possible combinations of x, the number of monitors, and y, the number of keyboards, the university can buy for the computer lab is 250x + 50y <= 4500

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Answer: $18.30

Step-by-step explanation:

The sprinkler cost 9.23, and the change is 9.07, so adding both of them equal $18.30

Answer 18.3

eeeeeeeeeeeeeeeeeeeeeeee

The average rate of change in the stock from hour 1 to hour 6 is -$0.20/hr.

What is average rate of change in stock?

We need to find the average rate of change of stock from 1 hour to 6 hours.

The value of stock was $11 in hour 1 and $10 in hour 6.

Average rate of change = Δy/ Δx

= $10 - $11 / 6-1

= - $1/5

= -$0.20 /hr

Hence, the average rate of change in the stock from hour 1 to hour 6 is -$0.20/hr.

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The given expression is in the form of the polynomial as -4x⁴+11x³-5x²+6 and the degree of the polynomial is 4.

Polynomial is the combination of variables and constants systematically with "n" number of power in ascending or descending order.

[tex]\rm a_1x+a_2x^2+a_3x^3+a_4x^4..........a_nx^n[/tex]

It is given that the polynomial expression is, (-4x² + 3x + 3)(x² - 2x + 2)

We have to simplify the expression by multiplying the expression as,

=-4x²(x² - 2x + 2)+3x(x² - 2x + 2)+3(x² - 2x + 2)

=-4x⁴+8x³-8x²+3x³-6x²+6x+3x²-6x+6

= -4x⁴+11x³-5x²+6

Thus, the given expression is in the form of the polynomial as -4x⁴+11x³-5x²+6 and the degree of the polynomial is 4.

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The number of players the team can bring to the tournament would be = 24 players

The softball game is the type of game that involves two teams which is made up of 9. - 10 players.

The total amount of money raised by a softball team=

$2089.50

The amount of money spent on rented bus = $1087.50

The amount left after rent deductions= 2,089.50 - 1,087.50 = 1,002

The amount budgeted for meals for each player= $41.75

The number of players that would be brought for tournament= 1,002/41.75

= 24 players.

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After solving the quadratic equation, the value of k will be equal to 71.

Equations are mathematical expressions that have two algebras on either side of an equal (=) sign. The expressions on the left and right are shown to be equal, demonstrating this relationship. L.H.S. = R.H.S. (left-hand side = right side) is a fundamental simple equation.

As per the given equation in the question,

4x² - 5x = -6

4x² - 5x + 6 = 0

k = b² - 4ac

⇒ (-5)² - 4(4)(6)

k = 25- 96

k = -71 or,

k = i(71)

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Answer:

9 4/6

Step-by-step explanation:

5 + 4 = 9

1/6 + 3/6 = 4/6

9 4/6

Hope this helps! :)

Answer:

Part A

7x² + 5xy – 3

Part B

2x² – 8xy + 8

Step-by-step explanation:

Part A

the canned food collected so far is the sum of the canned food the three friends have by combining the expression

5xy + 2 + 6x² – 5 + x²

= 6x² + x² + 5xy + 2 – 5

= 7x² + 5xy – 3

Part B

The total of cans the friend need to collect to meet their goal is the canned food collected so far minus their targeted goal

= 9x² – 3xy + 5 – (7x² + 5xy – 3)

= 9x² – 3xy + 5 – 7x² – 5xy + 3

= 9x² – 7x² – 3xy – 5xy + 5 + 3

= 2x² – 8xy + 8

i hope this helps

Answer:

1 = 45

2 = 75

3 = 60

4 = 41

5 = 71

6 = 109

Step-by-step explanation:

This may seem tricky at first, but if you follow the order of the numbers, you can find them fairly quickly using the values already given.

For angle 1:

The angle above it of 45 degrees is similar to angle 1, so that it automatically going to be 45

For angle 2:

The same concept for angle 1 applies for angle 2, so it will be 75 degrees.

For angle 3:

All triangles add up to 180 degrees. So, since we have angles 1, and 2, solve to find 3:

180 - 45 - 75 = 60

For angle 4:

All straight lines add up to 180 degrees. So solve to find angle 4 using the value we found for angle 3:

180 - 60 - 79 = 41

For angle 5:

Angle 5 is part of another triangle and we have two of the angles already. So solve to find angle 5 using the logic used to find angle 3:

180 - 41 - 68 = 71

For angle 6:

angles 5 and 6 are part of a straight line, so use the same logic for angle 4 and solve for angle 6:

180 - 71 = 109

Answer:

22, and -22

Step-by-step explanation:

22x22=484

-22x(-22)=484

The solution for this system of equation will be [tex]x=4, y=-3.[/tex]

We will solve the given system of equation by the method of substitution. Now we label the equations as  [tex]2x+y=5....(i)[/tex] and [tex]-3x-5y=3....(ii)[/tex].

Now from equation [tex](i)[/tex] we will find the value of [tex]y[/tex] which is [tex]5-2x[/tex]. Then we will substitute the value of [tex]y[/tex] in equation [tex](ii)[/tex].

So, [tex]-3x-5\times(5-2x)=3[/tex]

⇒ [tex]-3x-25+10x=3[/tex]

⇒ [tex]7x-25=3[/tex]

⇒ [tex]7x=28[/tex]

[tex]\therefore x =\frac{28}{7}=4....(iii)[/tex]

Now we will take the value of [tex]x[/tex] from equation equation [tex](iii)[/tex] and substitute in equation [tex](i)[/tex] to get the value of [tex]y[/tex].

So, [tex](2 \times 4)+y=5[/tex]

⇒ [tex]8+y=5[/tex]

⇒ [tex]y=8-5[/tex]

[tex]\therefore y=3[/tex]

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The area is 120 [tex]cm^{2}[/tex].

Area is the size of a two-dimensional surface, usually expressed in square units, such as square feet or square meters. It is the amount of two-dimensional space enclosed within a given set of boundaries. Area can be calculated for various shapes, including squares, rectangles, triangles, circles, and more complex shapes. Area is also a measure of the amount of space an object occupies. In mathematics, area is used to measure the size of a shape or region in a plane. It can also be used to calculate the size of a figure, such as the area of a triangle, or to measure the area of an enclosed space, such as a garden or a room.

Given:

AB = CD = 8cm

AD = BC = 12cm

EF = DH = 4cm

So, the required area is A = Area (ABCEFD) = Area (ABCD) + Area (CEFD)

Area of ABCD = Area (ABCD) = AB × BC

⇒ 12 × 8 = 96 [tex]cm^{2}[/tex]

Area of CEFD = Area (CEFD) = 0.5 (CD + EF) × HD

⇒ 0.5 × (8 + 4) × 4 = 24[tex]cm^{2}[/tex]

Now, the required area is

⇒ A = 96 [tex]cm^{2}[/tex] + 24 [tex]cm^{2}[/tex] = 120 [tex]cm^{2}[/tex]

Hence, the required area of the figure is 120 [tex]cm^{2}[/tex].

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Answer:

A

(will be continued)

Step-by-step explanation:

this is an exponential graph

The original mass is 7.71 because it is being multiplied by the percentage.

0.9333 in percentage form is 93.33

Since it is being multiplied, by the original mass this means that 93.33% of it is the amount being left over.

100% - 93.33% = 6.67%

this is the decrease in the amount of the thing

***tell me if i explained it clearly i'm not sure if i did

Answer:

4/5

Step-by-step explanation:

The width of the prism is x+2. The smallest dimension of an item or figure on a planar surface is its width.

When calculating the volume of a rectangular prism, we multiply the prism's length, width, and height.

A rectangular prism is a polyhedron in geometry that has two parallel and congruent bases. It also goes by the name cuboid. Six faces, each with a rectangle shape and twelve edges, make up a rectangular prism. It is referred to as a prism because of the length of its cross-section.

Given, the volume of the prism

= x³ + 2x²+ 20x - 24

length = (x- 6 )

height and width are equal then

h * w = x³ + 2x²+ 20x - 24 / (x - 6)

= (x + 2 ) (x + 2)

h = (x +2 )and

w = (x+2)

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Answer:

34 dollars and 6 cents

Step-by-step explanation:

1 percent = 0.26

0.26 x 31 = 8.06

26 + 8.06 = 34 dollars and 6 cents

I believe it is 34.06

The coordinates will be after applying the transformation, I(-5,0) --I'(0, -5), Y(0, 2) - -> Y'(2, 0) and T(4, 4) --> T'(4, 4).

It is defined as the change in coordinates and the shape of the geometrical body. It is also referred to as a two-dimensional transformation. In the geometric transformation, changes in the geometry can be possible by rotation, translation, reflection, and glide translation.

It is given that:

The graph is shown in the picture.

From the picture the coordinates are:

I(-5,0), Y(0, 2), and T(4, 4)

The transformation rule:

(x, y) --> (y, x)

I(-5,0) --I'(0, -5)

Y(0, 2) - -> Y'(2, 0) and

T(4, 4) --> T'(4, 4)

Thus, the coordinates will be after applying the transformation, I(-5,0) --I'(0, -5), Y(0, 2) - -> Y'(2, 0) and T(4, 4) --> T'(4, 4).

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Answer:

a) 45

b) 54

Step-by-step explanation:

a) To be able to round up to the nearest 10, the number in the "ones column" needs to be 5 at the minimum.

You could argue it could be a decimal point however, you shouldn't really have a decimal of a bead ( it's possible but it over complicates the answer ) and, it's to the nearest 10, not nearest one decimal point for example.

Therefore, the min is 45 beads

b) ( The above poster was correct oops, I made a silly mistake )

The max is 54 beads as if anything in the ones column is under 4, you can't round up to the nearest 10. Hence it remains as 50 when rounding

Therefore, the max is 54 beads