I need help!!!! I don’t understand and it’s very confusing

Answer:

A

Step-by-step explanation:

Volume of cone = (1/3) πr²h

Answer:

[tex] - 45[/tex]

[tex]2.25( - 2) = - 45 \\ - 45[/tex]

Question:

The relationship between t and r is expressed by the equation 2t+3r+6 = 0. If r increases by 4, which of the following statements about t must be true?

Answer:

The value of t is reduced by 6 when the value of r is increased by 4

Step-by-step explanation:

Given

[tex]2t + 3r + 6 = 0[/tex]

Required

What happens when r is increased by 4

[tex]2t + 3r + 6 = 0[/tex] -------- Equation 1

Subtract 2t from both sides

[tex]2t + 3r + 6 - 2t = 0 - 2t[/tex]

[tex]3r + 6 = - 2t[/tex] --- Equation 2

When r is increased by 4, equation 1 becomes

[tex]2T + 3(r+4) + 6 = 0[/tex]

Note that the increment of r also affects the value of t; hence, the new value of t is represented by T

Open bracket

[tex]2T + 3r+12 + 6 = 0[/tex]

Rearrange

[tex]2T + 3r+6 +12 = 0[/tex]

Substitutr -2t for 3r + 6 [From equation 2]

[tex]2T -2t +12 = 0[/tex]

Make T the subject of formula

[tex]2T = 2t - 12[/tex]

Divide both sides by 2

[tex]\frac{2T}{2} = \frac{2t - 12}{2}[/tex]

[tex]T = t - 6[/tex]

This means that the value of t is reduced by 6 when the value of r is increased by 4

[tex]a^{2} {c}^{2} - {a}^{2} {d}^{2} - {b}^{2} {c}^{2} + {b}^{2} {d}^{2} + 4abc[/tex]

Answer:

[tex]Expected \ mean = \dfrac{sum \ of \ values }{n}[/tex]

[tex]Expected \ mean = \dfrac{315 }{7}[/tex]

Expected mean = 45

The Chi - Square Value = 15.556

Conclusion:

We conclude that there is equal number of average interest in the course across all regions.  

Thus, the CFO is correct, the the frequencies in the regions are not significantly different by using a Chi-Square Goodness of Fit Test with a 1% significance level.

Step-by-step explanation:

From the question; Let state our null hypothesis and alternative hypothesis

Null Hypothesis

[tex]\mathbf{H_0:}[/tex]There is equal number of average interest in the course across all regions.  

Alternative Hypothesis

[tex]\mathbf{H_a:}[/tex] At least one of the region differs in average number of interest in the course.

The table can be better structured as :

Region          Enrollment

1                       45

2                       60

3                       30

4                       40

5                       50

6                       55

7                       35

From above; we know the number of sample = 7

Then our expected mean can be calculated as :

[tex]Expected \ mean = \dfrac{sum \ of \ values }{n}[/tex]

[tex]Expected \ mean = \dfrac{315 }{7}[/tex]

Expected mean = 45

SO, let's construct our Chi-Square  Statistics Test Table as follows:

Observed       Expected       Expected       (O-E)²         [tex]\dfrac{(O-E)^2}{E}[/tex]

(O)                         (E)            proportion    

45                          45           0.142857          0                   0

60                          45           0.142857       225                 5

30                          45           0.142857        225                5

40                          45           0.142857          25               0.556

50                          45           0.142857          25               0.556

55                          45           0.142857         100               2.222

35                          45           0.142857          100              2.222

                                                                                          15.556

The Chi - Square Value = 15.556

Degree of freedom = n- 1

Degree of freedom = 7 - 1

Degree of freedom = 6

Level of significance ∝ = 1% = 0.01

The Critical value of Chi Square test statistic at df = 6 and 0.01 significance level is 16.812

The Decision rule is to reject the Null hypothesis if The Chi Square test statistic X² > 16.812

Thus , since  the Chi Square test statistic is lesser than the critical value,

i.e  15.556 < 16.812 ,we accept null hypothesis [tex]\mathbf{H_0}[/tex]

Conclusion:

We conclude that there is equal number of average interest in the course across all regions.  

Thus, the CFO is correct, the the frequencies in the regions are not significantly different by using a Chi-Square Goodness of Fit Test with a 1% significance level.

Answer19/40=x/3.6

By cross multiplication

19*3.6=40*x

68.4 =40x

x=68.4/40

x=1.71

x=

Answer: C

Step-by-step explanation:

[tex]\frac{19}{40} = \frac{x}{3.6}[/tex]     solve by cross product

40x = 68.4   Divide both sides by 40

x =  1.71

Answer:

The percentage of adult female reaction times that lie between 140.5 and 648.1 milliseconds is 99.7%.

Step-by-step explanation:

The Empirical Rule states that, for a normally distributed random variable:

68% of the measures are within 1 standard deviation of the mean.

95% of the measures are within 2 standard deviation of the mean.

99.7% of the measures are within 3 standard deviations of the mean.

In this problem, we have that:

Mean = 394.3 ms

Standard deviation = 84.6 ms

Use the Empirical Rule to determine the approximate percentage of adult female reaction times that lie between 140.5 and 648.1 milliseconds.

140.5 = 394.3 - 3*84.6

So 140.5 is 3 standard deviations below the mean.

648.1 = 394.3 + 3*84.6

So 648.1 is 3 standard deviations above the mean.

By the Empirical Rule,

The percentage of adult female reaction times that lie between 140.5 and 648.1 milliseconds is 99.7%.

Answer:

1

Step-by-step explanation:

g(-4) means what is the y value when x is -4.

Find x=-4, and when x=-4. y=1

Answer:

1

Step-by-step explanation:

Answer:

(1,-7/2)

Step-by-step explanation:

The midpoint of (9,2)(-7,-9) is (1,-7/2)

Answer: r= 12.58m

Step-by-step explanation:

100% SURE

Answer:

a) [tex]V(t) = 24 - 2t[/tex]

b) As t increases from 3 to 6, v varies from 18 gallons to 12 gallons.

Step-by-step explanation:

The volume of the tank in terms of the time can be described by the following equation:

[tex]V(t) = V(0) - at[/tex]

In which V(0) is the initial volume and a is the hourly decrease rate.

a. Write a formula that expresses v in terms of t.

The tank initially contains 24 gallons of water, which means that [tex]V(0) = 24[/tex]

Drains at a constant rate of 2 gallons per hour, so [tex]a = 2[/tex]

Then

[tex]V(t) = V(0) - at[/tex]

[tex]V(t) = 24 - 2t[/tex]

b. As t increases from 3 to 6, v varies from _________ to _________

[tex]V(t) = 24 - 2t[/tex]

[tex]V(3) = 24 - 2*3 = 18[/tex]

[tex]V(6) = 24 - 2*6 = 12[/tex]

So as t increases from 3 to 6, v varies from 18 gallons to 12 gallons.

Answer:

so the axis of symmetry is x=4

Answer: X = 4

Explanation: Hope it helps you♡

Answer:

B. (f - g)(x) = [tex]3^x-2x+14[/tex]

Step-by-step explanation:

→Set it up, like so:

[tex](3^x+10)-(2x-4)[/tex]

→Distribute the -1 to (2x - 4):

[tex]3^x+10-2x+4[/tex]

→Add like terms (10 and 4):

[tex]3^x-2x+14[/tex]

Answer:

y = 5x + 20

Step-by-step explanation:

The initial percent is 20.

Every minute, the percent goes up 5%, so the slope is 5.

So the equation of the line is y = 5x + 20.

Answer:

Ratio of Able's score to Ben=6:1

Ratio of Ben's score to Cal's=1:2

Ratio of able's score to ben;s score to cal's score=6:1:2

Step-by-step explanation:

Let Ben's score =x

Able scored six times Ben's score

Able=6*x

=6x

Cal scored a third of Able's score

Cal=1/3 of 6x

=1/3(6x)

Ratio of Able's score to Ben

6x:x

=6:1

Ratio of Ben's score to Cal's score

x:1/3(6x)

=x:6x/3

=x:2x

=1:2

Ratio of able's score to ben;s score to cal's score=6:1:2

Answer:

900 eggs

Step-by-step explanation:

45/50 are marketable

divide the top and bottom by 5

9/10

Multiply this fraction by the 1000 eggs laid

9/10 *1000

900 eggs will be marketable

Answer:

900

Step-by-step explanation:

Answer:

Step-by-step explanation:

line equation:  y=mx + C

substitute given values

-7 = -3*0 + C

C=y= -7      ANS

Answer:

P = 0.1764

The events are dependent

Step-by-step explanation:

We have a total of 9 + 6 + 3 = 18 stuffed animals.

The probability of the first animal pulled being a bear is:

P(bear) = N(bear) / N(total)

P(bear) = 9 / 18 = 0.5

Then, for the second animal, we now have only 17 stuffed animals in total.

So the probability of the second animal pulled being a lion, given the first animal was a bear, is:

P(lion | bear) = N(lion) / N(total)

P(lion | bear) = 6 / 17 = 0.3529

So the final probability is the product of these probabilities:

P = P(bear) * P(lion | bear) = 0.5 * 0.3529 = 0.1764

To find if the events are dependent or independent, let's find the probability of the first pick being a lion:

P(lion) = N(lion) / N(total)

P(lion) = 6 / 18 = 0.3333

The probability of picking a lion is different from the probability of picking a lion given we already picked a bear, so the events are dependent.

Answer:

18.66 ft/s

Step-by-step explanation:

The distance between you and the elevator is given by:

[tex]h=\sqrt{x^2+y^2}[/tex]

The rate of change for the distance between you and the elevator is given by:

[tex]\frac{dh}{dt}=\frac{dh}{dy}*\frac{dy}{dt}[/tex]

[tex]-16=\frac{dh}{dy}*\frac{dy}{dt}[/tex]

[tex]\frac{dh}{dy}=\frac{d}{dy} (\sqrt{x^2+y^2})\\[/tex]

Applying the chain rule:

[tex]u=x^2+y^2\\\frac{dh}{dy}=\frac{d\sqrt u}{du} *\frac{du}{dy}\\\frac{dh}{dy}=\frac{1}{2\sqrt u} *2y\\\frac{dh}{dy}=\frac{y}{\sqrt {(x^2+y^2)}}[/tex]

Therefore, at x=300 and y = 500, dy/dt is:

[tex]-16=\frac{y}{\sqrt {(x^2+y^2)}}*\frac{dy}{dt}\\-16=\frac{500}{\sqrt {(300^2+500^2)}}*\frac{dy}{dt}\\\frac{dy}{dt}=-18.66\ ft/s[/tex]

The elevator is descending at 18.66 ft/s.

Answer:

Step-by-step explanation:

Twelve years ago Jane was five times as old as Anne.  

 J-12=5(A-12)

In three years time, Anne will be half of Jane's age.  

A+3=1/2(J+3)

Simplify and solve this system of equations:

 J-12=5(A-12)

A+3=1/2(J+3)

Answer:

Circle

Step-by-step explanation:

r = 2 cos θ

Multiply both sides by r.

r² = 2r cos θ

Convert to rectangular.

x² + y² = 2x

x² − 2x + y² = 0

Complete the square.

x² − 2x + 1 + y² = 1

(x − 1)² + y² = 1

This is a circle with center (1, 0) and radius 1.

The given function r = 2 cos θ is a circle with a center (1, 0) and radius of 1.

A circle is a shape consisting of all points in a plane that are given the same distance from a given point called the center.

Given function is r = 2 cos θ

Now, Multiply both sides by r.

r² = 2r cos θ

Convert to rectangular form;

x² + y² = 2x

x² − 2x + y² = 0

Using Complete the square.

x² − 2x + 1 + y² = 1

(x − 1)² + y² = 1

Hence, This is a circle with a center (1, 0) and radius of 1.

Learn more about circle here;

brainly.com/question/12512221

#SPJ2

Answer:

So the diagram couldn't come due to coronavirus?

Answer:

there is no diagram

Step-by-step explanation:

Answer:

a) We can not estimate the probability.

b) Zero probability.

c) There is a probability between 95% and 99% that they have between 475 and 525 customers on a given day.

Step-by-step explanation:

a) We can not said nothing because we only know the average of customers per day. We need to know the probability distribution of the amount of customers per day to answer this question.

b) Now that we know that the variance is 100, although we do not know the exact distribution of the values, we can use the empirical rules to estimate the probability of having at least 700 customers on a given day.

If the variance is 100, the standard deviation is √100=10.

Applying the empirical rule (68-95-99.7 rule), we know that there is probability 0.15% of having at least 500+3*10=530 customers per day (more than 3 deviations from the mean).

Then, we can conclude that the probability of having at least 700 customers per day is zero.

c) To estimate this probability, we have to calculate how many deviations from the mean this values represent:

[tex]\Delta_1=475-500=-25=2.5\sigma\\\\\Delta_2=525-500=25=2.5\sigma[/tex]

We have an interval that have a width of ±2.5 deviations from the mean.

For 2 deviations from the mean, it is expected to have 95% of the data.

For 3 deviations from the mean, it is expected to have 99.7% of the data.

Then, for the interval 475 to 525, we can estimate a probability between 95% and 99%.

Answer:

Please see steps below

Step-by-step explanation:

In order to factor by grouping, we divide the four terms given into two groups, and extract on each group any common factor  we can.

In our example, we can select the terms: [tex]w^2[/tex]  and [tex]w[/tex] as one of our groups, and [tex]3w[/tex] and 3 in the other group. Then we re-organize the expression as:

[tex](w^2+w)+(3x+3)[/tex]

Now we extract from the first binomial group, the factor [tex]w[/tex] as a common factor of both terms, and from the second group we extract the factor "3" as common factor of those two terms:

[tex](w^2+w)+(3x+3)\\w(w+1)+3(w+1)[/tex]

We notice now that after the extraction, we are left with two exactly equal binomial factors [tex](w+1)[/tex] that appeared in the first group and in the second group. We proceed then to extract it as common factor for the two groups:

[tex]w(w+1)+3(w+1)\\(w+1)(w+3)[/tex]

this last product of two binomials ([tex](w+1)\,(w+3)[/tex] is the result of factoring the original expression.

Answer:

C. 1/25

Step-by-step explanation:

5^-2=5^(2*-1)

5^2=25

25^-1=1/25

Answer:

It is C 1/25 because it won't be -25 because a negative times a negative is a positive

Step-by-step explanation:

Answer:

4 ( a+2)

Step-by-step explanation:

The average rate of change is

(f(a) - f(2))/(a-2)

f(a) = 4a^2 -8

f(2) = 4*2^2 -8 = 4*4 -8 = 16-8 = 8

(4a^2 - 8  - 8))/(a-2)

(4a^2 -16) / (a-2)

Factor the numerator

4( a^2 -4) / (a-2)

4( a-2)(a+2) / (a-2)

Cancel

4 ( a+2)

3s represents three times Sydney's age. Sydney's age is symbolized with an S.

Answer:

see below

Step-by-step explanation:

i is the imaginary number and it represents the square root of -1

Answer:

The answer is A

Step-by-step explanation:

[tex]the \: answer \: is \: 10 \\ please \: see \: the \: attached \: picture \: for \\ full \: solution \\ hope \: it \: helps[/tex]

Answer:

10 is the answer for this question.