The random variable x represents the number of computers that families have along with the corresponding probabilities. Find the mean and standard deviation for the random variable x. Group of answer choices mean: 1.39; standard deviation: 0.80 mean: 1.18; standard deviation: 0.64 mean: 1.39; standard deviation: 0.64 mean: 1.18; standard deviation: 1.30

Answer: [tex]\frac{-7+\sqrt{49-4(15)(-12)} }{30}[/tex]

Step-by-step explanation:

Use the quadratic formula:

[tex]\frac{-b+-\sqrt{b^{2}-4(ac) } }{2a}[/tex]

Substitute the values, A = 15, b = 7, c = -12

[tex]\frac{-7+-\sqrt{7^{2}-4*(15*-12) } }{2*15}[/tex]

Simplify to answer:

[tex]\frac{-7+49-4(15)(-12)}{30}[/tex]

I hope this helps!

Answer:

x = 10

y =10√2

Step-by-step explanation:

 The ratio of the sides of 45°- 45° - 90° triangle is a : a :  a√2

The side opposite to angle 45°  is a

a = 10

⇒ x =  a

  [tex]\sf \boxed{\bf x = 10}[/tex]

The side opposite to 90° is a√2

  y = a√2

    = 10√2

[tex]\sf \boxed{\bf y= 10\sqrt{2}}[/tex]

Answer:

Step-by-step explanation:

is an isosceles right triangle, so x = 10

to find y we use pythagoras

y = √(10²+10²)

y = √200

y = 14.1 or 10√2

A conditional probability of an event tells us that the event has already occured.

Given a _______ probability of an event is a ............. other event has already occurred.

We have to fill the blank with appropriate term or word associated with probability.

The right term is conditional.

Conditional probability of an event is a probability obtained with knowledge that some other event has already occured.

It is denoted as P(A I B).

It satisfies the following equation:

P(AIB)=P(A and B ) / P(B)

where P( A and B) is the probability of A and B together.

Hence conditional probability of an event is obtained with knowledge that some other event has already occured.

Learn more about conditional probability at https://brainly.com/question/10739997

#SPJ4

Answer:

5/2

Step-by-step explanation:

Answer:

1 3/4 or 1.75

Step-by-step explanation:

Formula: y1-y2/x1-x2

Plug in the given coordinates: y1 = -3, y2 = 4, x1 = 2, x2 = 6

-3-4/2-6 = -7/-4 = 7/4 = 1 3/4 or 1.75

The rule which describe the composition of transformations that

maps ΔBCD to ΔB"C"D" is:

Reflection across the y-axis composition translation of 6 units x,

negative 5 units y ⇒ last answer

Step-by-step explanation:

Let us revise the reflection across the y-axis , horizontal translation

and vertical translation

1. If point (x , y) is reflected across the y-axis, then its image is (-x , y)

2. If point (x , y) is translated h units to the right, then its image is

  (x + h , y), if translated h units to the left, then its image is (x - h , y)

3. If point (x , y) is translated k units up, then its image is (x , y + k),

  if translated k units down, then its image is (x , y - k)

∵ The vertices of triangle BCD are (1 , 4) , (1 , 2) , (5 , 3)

∵ The vertices of triangle B'C'D' are (-1 , 4) , (-1 , 2) , (-5 , 3)

∵ The x-coordinates of the vertices of Δ B'C'D' have the same

  magnitude of x-coordinates of Δ BCD and opposite signs

∴ Δ B'C'D' is the image of Δ ABC after reflection across the y-axis

∵ The vertices of triangle B'C'D' are (-1 , 4) , (-1 , 2) , (-5 , 3)

∵ The vertices of triangle B''C''D'' are (5 , -1) , (5 , -3) , (1 , -2)

∵ The image of -1 is 5 and the image of -5 is 1

∴ The x-coordinates of the vertices of triangle B'C'D' are added by 6

∵ The image of 4 is -1 , image of 2 is -3 and the image of 3 is -2

∴ The y-coordinates of the vertices of triangle B'C'D' are subtracted

  by 5

∴ Δ B"C"D" is the image of Δ B'C'D' by translate 6 units to the right

 and 5 units down ⇒ (x + 6 , y - 5)

The rule which describe the composition of transformations that

maps ΔBCD to ΔB"C"D" is:

Reflection across the y-axis composition translation of 6 units x,

negative 5 units y

Learn more about reflection here brainly.com/question/11203617

#SPJ1

The composition of transformations that maps BCD to B"C"D" is described by the following rule:

Composition translation of 6 units x, negative 5 units y across the y-axis last response

Let us rewrite the y-axis reflection, horizontal translation, and vertical translation.

1. If point (x, y) is mirrored across the y-axis, the image of that point is (-x , y)

2. If point (x, y) is translated h units to the right, its image is (x + h, y), and if it is translated h units to the left, its image is (x + h, y) (x - h , y)

3. If point (x, y) is translated k units up, its image is (x, y + k), but if it is translated k units down, its image is (x , y - k)

∵ Triangle BCD has (1, 4) vertices, (1, 2) vertices, and (5, 3) vertices. Triangle B'C'D' has (-1, 4) vertices, (1, 2) vertices, and (5, 3) vertices. The x-coordinates of the B'C'D' vertices have the same magnitude as the x-coordinates of BCD and opposite signs. B'C'D' is the picture of ABC after it has been reflected across the y-axis.

The vertices of triangle B'C'D' are (-1, 4), (-1, 2), (-5, 3), (1, -2)

The vertices of triangle B"C"D" are (5, -1), (5, -3), (1, -2)

The x-coordinates of the triangle B'C'D' vertices are added by 6.

The image of 4 is -1, the image of 2 is -3, and the image of 3 is -2.

The y-coordinates of triangle B'C'D' vertices are subtracted by 5.

∴ Δ B"C"D" is the image of Δ B'C'D' by translating 6 units to the right

and 5 units down ⇒ (x + 6 , y - 5)

The rule which describe the composition of transformations that

maps ΔBCD to ΔB"C"D" is:

Reflection across the y-axis composition translation of 6 units x,

negative 5 units y

Learn more about reflection here:

brainly.com/question/11203617

#SPJ1

The dividend is [tex]2x^2+9x+7[/tex] while the divisor is x + 1

Option A is correct

The coefficient outside the division block is -1.

This means that the divisor = x + 1

Also, the coefficients of the dividend are:

2, 9, 7

The highest exponent is 2 since there are three terms in the polynomial. Three terms show that the expression is a quadratic expression

Therefore, the dividend is [tex]2x^2+9x+7[/tex]

Learn more on synthetic division of polynomial here: https://brainly.com/question/24662212

#SPJ1

The results of the survey best illustrate the framing effect.

People make choices based on whether possibilities are given with positive or negative connotations, such as as a gain or a loss, according to a cognitive bias known as the framing effect.

When provided with a positive frame, people tend to avoid danger, but when offered with a negative frame, they tend to seek out hazards.

The scenario of framing effect defines gain and loss as descriptions of results.

The idea aids in the development of framing effect understanding in social movements as well as in the creation of political opinion, where spin plays a significant role in political opinion polls that are framed to encourage a response advantageous to the group that commissioned the poll. It has been asserted that the framing effect is invalidating political polls.

Learn more about framing effect here:

https://brainly.com/question/2444365

#SPJ4

Answer:

5 days

(the exact number of days below)

Step-by-step explanation:

65/7=9.28571429

9.28571429 sec = 1 dollar

464285.715 seconds=50000 dollars

464285.715 seconds=5.373677256944 days

Answer:

The degree of polynomial is 5.

Step-by-step explanation:

I suppose the polynomial is [tex]\displaystyle{5x^2+8x^3+4-6x^2-3x^5}[/tex]. To find the which degree this polynomial is, we consider the highest exponent of the term which is [tex]\displaystyle{3x^5}[/tex], the 5 is our highest degree of the term and thus, 5 is our highest degree of polynomial.

Answer:

5

Step-by-step explanation:

I'm assuming that the 5 in "3x5​" is supposed to be a exponent. The degree of the polynomial is the greatest of the exponents (powers) of its various terms.

Answer:

B

Step-by-step explanation:

[tex]\frac{x}{x-3}[/tex] × [tex]\frac{2x}{x+5}[/tex] ( no factors cancel on numerator / denominator )

= [tex]\frac{x(2x)}{(x-3)(x+5)}[/tex]

= [tex]\frac{2x^2}{x^2+2x-15}[/tex]

Answer:

[tex]a_{n}[/tex] = 3 [tex](-2)^{n-1}[/tex]

Step-by-step explanation:

there is a common ratio between consecutive terms , that is

- 6 ÷ 3 = 12 ÷ - 6 = - 24 ÷ 12 = 48 ÷ - 24 = - 2

this indicates the sequence is arithmetic with explicit rule

[tex]a_{n}[/tex] = a₁ [tex](r)^{n-1}[/tex]

where a₁ is the first term and r the common ratio

here a₁ = 3 and r = - 2 , then

[tex]a_{n}[/tex] = 3 [tex](-2)^{n-1}[/tex]

Answer:

[tex]\sf \dfrac{-3}{2}(-2)^n[/tex]

Step-by-step explanation:

Explicit formulas are used to represent all the terms of the geometric sequence with a single formula.

  [tex]\sf \boxed{\bf t_n = ar^{n-1}}[/tex]

a is the first term.

r is the common ratio.

r = second term ÷ first term.

   3 , - 6 , 12, - 24, 48 ,........

a = 3

r = -6 ÷ 3 = -2

         [tex]\sf t_n = 3*(-2)^{(n-1)}\\\\[/tex]

             [tex]\sf = 3*(-2)^{n}*(-2)^{-1}\\\\ =3*(-2)^n*\dfrac{-1}{2}\\\\= \dfrac{-3}{2}(-2)^n[/tex]

Check:

[tex]\sf t_1 =\dfrac{-3}{2}*(-2)^1=\dfrac{-3}{2}*(-2) = 3\\\\\\t-2 = \dfrac{-3}{2}*(-2)^2 = \dfrac{-3}{2}*4=-6\\\\\\t_3=\dfrac{-3}{2}*(-2)^3=\dfrac{-3}{2}*(-8)=12[/tex]

Answer:

Step-by-step explanation:jneke

There is no such value of 'a' such that f(x) = 9x² + 4 and g(x) = (3x - a)² are equivalent.

Two polynomials are said to be equivalent only when the coefficients of all powers of x are equal for both the polynomials.

In the question, we are asked is there a value of 'a' such that f(x) = 9x² + 4 and g(x) = (3x - a)² are equivalent.

We know that two polynomials are said to be equivalent only when the coefficients of all powers of x are equal for both the polynomials.

Thus to check, we expand g(x), using the formula (p - q)² = p² + q² - 2pq.

g(x) = (3x - a)²,

or, g(x) = (3x)² + (a)² - 2(3x)(a),

or, g(x) = 9x² + a² - 6ax.

For f(x) = 9x² - 4, and g(x) = (3x - a)² to be equivalent,

As we need two different values of, 'a' at the same time, which ain't possible, thus we can say that there is no such value of 'a' such that f(x) = 9x² + 4 and g(x) = (3x - a)² are equivalent.

Learn more about equivalent polynomials at

https://brainly.com/question/10191748

#SPJ2

Answer:

sin-1 (24/25).

Step-by-step explanation:

We are given the opposite side  to the given angle (24 ft) and the hypotenuse (25 ft) .

sin = opposite / hypotenuse

- so it is  sin-1 (24/25).

Answer:

3/5

Step-by-step explanation:

the chance of landing on an even number (2 or 4) is 2/5

the chance of landing on the unshaded section (3) is 1/5

add the 2 together since the problem said "or" to get 3/5

By the use of factor decomposition and algebra properties, we conclude that the rational number 48/192 is equal to the rational number 1/4.

In this question we should simplify a rational number into its simplest form based on two facts. First, that all natural numbers except 1 and the prime numbers are products of prime numbers and, second, the simplification of the fraction can be done by using the following algebra property:

(a · c)/(b · c) = a/b, where a, b, c are natural numbers.     (1)

Along with power properties.

Now we proceed to simplify the rational number:

48/192 = (2⁴ × 3) / (2⁶ × 3)

48/192 = 1 / 2²

48/192 = 1 / 4

By the use of factor decomposition and algebra properties, we conclude that the rational number 48/192 is equal to the rational number 1/4.

To learn more on fractions: https://brainly.com/question/10354322

#SPJ1

Answer:

4

Step-by-step explanation:

The stock worth when she sells it eight years later $545, If the stock decreases at a rate of 15% per year for eight years.

According  to the question,

Petra opens her mail one day to find that an anonymous donor has given her $3000 cash. She sets aside $1000 to refurnish her apartment, and decides to invest the other $2000.

If the stock decreases at a rate of 15% per year for eight years. In order to find the stock worth when she sells it eight years later we have the formula

Value of stock after 'n' years = Principal[1-Rate/100]ⁿ

Value of stock after '8' years = 2000[1-15/100]⁸

= 2000[1-0.15]⁸

=2000[0.85]⁸

=2000[0.2725]

=545$

Hence, the stock worth when she sells it eight years later $545, If the stock decreases at a rate of 15% per year for eight years.

Learn more about stock decreases here

https://brainly.com/question/13939400

#SPJ4

The NBA league exhibits more competitive balance.

The chance that each team in a league has of winning the title is referred to as competitive balance. The championship would be won by each team on a regular basis in an ideal competitive environment. In contrast, if there was no balance between the two types of competition, the same team would consistently prevail.

Competitive balance is often regarded as a desirable trait because too much predictability makes fans of the lesser franchises angry and fans of the defending champions complacent, which lowers interest in the sport as a whole.

The "Noll-Scully" measure is the competitive balancing metric that is most frequently used in sports. The winning percentage of each league team's standard deviation (SD) is used to compute it. The SD is then divided by what it would be if all teams had equal talent and the outcomes were entirely random.

For NBA team, competitive balance = 0.134/32*82 = 0.343

For EPL team, competitive balance = 0.158/20*38 = 0.30

Learn more about competitive balance here:

https://brainly.com/question/24696035

#SPJ1

                                                                  n=8

                                                                  n=-6

A number line is a horizontal line with evenly spaced number increments. The numbers on the line will determine how the number on the line can be answered.

The numbers on the number line increase as one moves from left to right and decrease as one moves from right to left.

A modulus function is a function that returns the absolute value of a number or variable. It yields the magnitude of the number of variables. It is also known as an absolute value function. This function's output is always positive, regardless of the input.

Open modulus with a positive sign.

                 5-|n-1|=-2

                -|n-1|=-2-5

                 n+1= 7

                 n= 8

Open modulus with a  negative sign.

                5-|n-1|=-2

                -|n-1|=-2-5

                 n-1= -7

                 n= -6

To know more about the  number line visit:

https://brainly.com/question/12801963

#SPJ4

Hello,

Pythagorean theorem :

x² = 8² + 8²

x² = 64 + 64

x² = 128

x = √128

x = √(64 × 2)

x = √(8² × 2)

x = 8√2

→ Answer D

#6

Yes

Direct variation because Time increases cupcakes increases and vice versa

#B

Constant of proportionality represents the amount of time required per cupcakes

#7

Yes we can find it

We have to check the x and y values of the ordered pairs (x,y)

If y is decreasing with respect to increase in x then it's inverse variation

Percentages are used to show the fraction of a thing. For example, if 5 students out of 20 like math, the percentage is 5/20 x 100= 25%

This refers to the number of ratios that is described as a fraction of 100 and is denoted by the sign %.

Hence, we can see that although your question is incomplete, I gave you a general overview of percentages for a better understanding of the concept.

Read more about percentages here:

https://brainly.com/question/16865197

#SPJ1

Kira's time exercising every day can be represented as t  ≥ 40 because she exercises for 40 minutes or more.

This situation can be represented with an inequality. An inequality is an expression that is used to represent variables. This type of expression uses symbols such as >, < or ≥ to represent different variable values.

The inequality represented in this situation implies that Kira exercises is equal or more time than 40 minutes every day.

Learn more about time in: brainly.com/question/26941752

#SPJ1

The probability that one would have selected 2 five-dollar bills is; 1/4.

It follows from the task content that the piggy bank contains; 4 one-dollar bills and 4 five-dollar bills to make a total of 8 bills.

Hence, provided the probability events are carried out with replacement, the probability to have selected 2 five-dollar bills is;

= 4/8 × 4/8

= 1/4.

Read more on probability;

https://brainly.com/question/24756209

#SPJ1

Answer:

1/4

Step-by-step explanation:

Answer:

x=1/3

Step-by-step explanation:

(2/x)+4=3^3+1

(2/x)+4=10

(2/x)=6

2=6x

1/3=x

x=1/3

There is also a possibility that you meant to write 2/(x+4)=3^2+1

2/(x+4)=3^2+1

2/(x+4)=10

2=10x+40

-38=10x

x=-3.8

Answer: -35/16

Step-by-step explanation:

i just took the test:)

Answer:

1)3×-8

-24

Step-by-step explanation:

2)bshejejnenenejejkejehrh

The measure represents the standard deviation of the sample means and is used in place of the population standard deviation when the population parameters are unknown is; t-test.

A hypothesis test for a population mean when In the case that the population standard deviation, σ, is unknown, carrying out a hypothesis test for the population mean is done in similarly like the population standard deviation is known. A major distinctive property is that unlike the standard normal distribution, the t-test is invoked.

Read more on t-test;

https://brainly.com/question/6501190

#SPJ1

Answer:

standard error of the mean

Step-by-step explanation:

Plato/Edmentum

Answer:

15

Step-by-step explanation:

First side is 20

Second side is 20 * (3/2), as it is 1 and 1 half times longer than the first

Second side is 30(as calculated above)

65-20-30 = 15

The Number of people is 12 when time taken is 2 hours.

According to the statement

Time taken when 10 people works is 3 hours

Time taken when 5 people works is 8 hours

Then we have to find the number of peoples when time taken is 2 hours.

So, average time that for which single person works is 180 min/ 10 = 18 min.

It means the average time for single person works is 18 min in case of 10 people.

and one thing is clear that the number of people is greater than 10 people when time taken is 2 hours.

So, The Number of people is 12 when time taken is 2 hours.

Learn more about AVERAGE here https://brainly.com/question/8728504

#SPJ4

Whenever two or more lines intersect at a point, an angle is usually produced. And some of these angles formed may have common properties, and thus be congruent.

The appropriate reasons for the given statements in the question are given below:

         STATEMENT                                          REASON

1. <1 ≅ <2                                                Vertical Angle theorem

2. <1 and <2 are complementary            

   <2 and <3 are complementary        Congruent Complements Theorem

3. <1 and <2 are supplementary              

   <2 and <3  are supplementary        Congruent Supplements

4. <1 and <2 are right angles               All Right Angles are Congruent

5. <1 ≅ <2,

   <1 and <2    are supplementary         If two angles are congruent and

                                                               supplementary, then each angle is

                                                               a right angle.

For more clarifications on the properties of complementary and supplementary angles, visit: https://brainly.com/question/14941189

#SPJ1