Repair calls are handled by one repairman at a photocopy shop. Repair time, including travel time, is exponentially distributed, with a mean of 1.1 hours per call. Requests for copier repairs come in at a mean rate of 1.6 per eight-hour day (assume Poisson). Determine the following:

Required:
a. Determine the average number of customers awaiting repairs.
b. Determine system utilization.
c. Determine the amount of time during an eight-hour day that the repairman is not out on a call.
d. Determine the probability of two or more customers in the system.

Hey there! I'm happy to help!

We see that if the river isn't moving at all the boat can move at 18 mph (most likely because it has an engine propelling it.)

We want to set up a proportion where our 21 miles downstream time is equal to our 15 miles upstream time so we can find the speed. A proportion is basically showing that two ratios are equal. Since our downstream distance and upstream distance can be done in the same amount of time, we will write it as a proportion.

We want to find the speed of the river. We will use r to represent the speed of the river. When going downstream, the boat will go faster, so it will have a higher mph. So, our speed going down is 18+r. When you are going upstream, it's the opposite, so it will be 18-r.

[tex]\frac{distance}{speed} =\frac{21}{18+r} = \frac{15}{18-r}[/tex]

So, how do we figure out what r is now? Well, one nice thing to know about proportions is that the product of the items diagonal from each other equals the product of the other items. Basically, that means that 15(18+r) is equal to 21(18-r). This is a very nice trick to solve proportions quickly. We see that we have made an equation and now we can solve it!

15(18+r)=21(18-r)

We use the distributive property to undo the parentheses.

270+15r=378-21r

We subtract 270 from both sides.

15r=108-21

We add 21 to both sides.

36r=108

We divide both sides by 36.

r=3

Therefore, the speed of the river is 3 mph.

You also could have noticed that 18mph to 21 mph is +3, and 18mph to 15 mph -3 in -3 mph, so the speed of the river is 3 mph. That would have been a quicker way to solve it XD!

Have a wonderful day!

Answer:

c and I will talk to you later today or tomorrow morning and then I will

Step-by-step explanation:

email to you later today to see you and the kids are doing well and that you

Answer:

x=98°

Step-by-step explanation:

The angles of a triangle must equal 180°.

To get the third angle (G) you must do: 180°-53°-45°

That will give you 82°

Anglr G and angle x create a straight line which is 180°.

so to get the answer you must do 180°-G=x

180°-82°=98°

Therefore x=98°

Answer: 22.3 quarter

Step-by-step explanation:

Answer:

13.896 kg

Step-by-step explanation:

Answer:

  A.  (2, 4)

Step-by-step explanation:

The ordered pairs represent (x, y). Since you have y =2x, this is the same as ...

  (x, 2x)

That is, the second number in the pair needs to be twice the first number in the pair. Since you know your times tables, you know that this is not the case for (1, 0), (10, 5) or (4, 12). Those values of x would give (1, 2), (10, 20), (4, 8).

It is the case that you have (x, 2x) for (2, 4).

The point (2, 4) lies on the graph of y = 2x.

Assuming the coin is not weighted and is a fair and standard coin - the chance of flipping head is 1/2. You can either flip head or tails, there are no other possible outcomes.

Answer:

Step-by-step explanation:

[tex]x + 3 = 6[/tex]

Move constant to R.H.S and change its sign:

[tex]x = 6 - 3[/tex]

Calculate the difference

[tex]x = 3[/tex]

Hope this helps...

Good luck on your assignment..

Answer:

[tex]\boxed{\sf \ \ \ a=-2, \ b = 1 \ \ \ }[/tex]

Step-by-step explanation:

Hello,

saying that the function is continuous means that you cannot have a "jump" in the graph of the function

so we want

a*(-3)+b=7 and a*4+b=-7

it comes

   (1) -3a + b = 7

   (2) 4a + b = -7

(2)-(1) gives 4a + b + 3a - b =7a = -7-7 = -14

so a = -14/7 = -2

we replace in (1)

b = 7 + 3*(-2) = 7 - 6 = 1

hope this helps

Answer:

873

Step-by-step explanation:

so the equation is: 5x+1

sum is:

[tex] \frac{first \: one \: + \: last \: one}{2} \times quantity \: of \: terms \\ [/tex]

we have 6( 5×1+1) to 91 (5×18+1)

so we have 18 terms

then:

[tex] \frac{91 + 6}{2} \times 18 = 873[/tex]

Answer:

a) [tex]654.16-2.01\frac{165.4}{\sqrt{52}}=608.06[/tex]    

[tex]654.16+2.01\frac{165.4}{\sqrt{52}}=700.26[/tex]    

b) [tex]n=(\frac{1.960(175)}{25})^2 =188.23 \approx 189[/tex]

So the answer for this case would be n=189 rounded up to the nearest integer

Step-by-step explanation:

Part a

[tex]\bar X=654.16[/tex] represent the sample mean

[tex]\mu[/tex] population mean (variable of interest)

s=165.4 represent the sample standard deviation

n =52represent the sample size  

The confidence interval for the mean is given by the following formula:

[tex]\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}[/tex]   (1)

The degrees of freedom aregiven by:

[tex]df=n-1=52-1=51[/tex]

Since the Confidence is 0.95 or 95%, the significance [tex]\alpha=0.05[/tex] and [tex]\alpha/2 =0.025[/tex], and the critical value would be [tex]t_{\alpha/2}=2.01[/tex]

Now we have everything in order to replace into formula (1):

[tex]654.16-2.01\frac{165.4}{\sqrt{52}}=608.06[/tex]    

[tex]654.16+2.01\frac{165.4}{\sqrt{52}}=700.26[/tex]    

Part b

The margin of error is given by this formula:

[tex] ME=z_{\alpha/2}\frac{s}{\sqrt{n}}[/tex]    (a)

And on this case we have that ME =25 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

[tex]n=(\frac{z_{\alpha/2} s}{ME})^2[/tex]   (b)

The critical value for this case wuld be [tex]z_{\alpha/2}=1.960[/tex], replacing into formula (b) we got:

[tex]n=(\frac{1.960(175)}{25})^2 =188.23 \approx 189[/tex]

So the answer for this case would be n=189 rounded up to the nearest integer

Answer:

4,224 in ^3

Step-by-step explanation:

5184-960 (subtract the cut-out from the entire shape)

Answer:

(14,4) (21, 6) (28,8) If they had six losses, they would have 21 wins

Step-by-step explanation:

According to the information given, for every 7 wins, they lose 2 games. That means in order to finish the table, we have to find multiples of 7 and 2. If they won 14 games, they would have 4 losses. This is because since 14 is twice the value of 7, they would have lost twice the number of games.

The next would be 21 wins since 7x3 is 21 and 6 losses since 2x3 is 6

The last one would be 28 wins (7x4) and 8 losses (2x4)

If they had six losses, they would have 21 wins

Answer:

A. f(x) = x^2 + 4x + 3

D. f(x) = -2x^2 - 8x + 1

Step-by-step explanation:

The axis of symmetry is found by h = -b/2a  where ax^2 +bx +c

A. f(x) = x^2 + 4x + 3

  h = -4/2*1 = -2    x=-2

B. f(x) = x^2 - 4x - 5

h = - -4/2*1 = 4/2 =2  x=2  not -2

C. f(x) = x^2 + 6x + 2

h =  -6/2*1 = -3/2 =  x=-3/2  not -2

D. f(x) = -2x^2 - 8x + 1

h = - -8/2*-2 = 8/-4 =-2  x=-2  

E. f(x) = -2x^2 + 8x - 2

h = - 8/2*-2 = -8/-4 =2  x=2  not -2

Answer:

Hey there! The answer to this question is

A. f(x) = x^2 + 4x + 3

D. f(x) = -2x^2 - 8x + 1

Answer:

(a) The probability that a randomly selected Time interval between irruption is longer than 84 minutes is 0.3264.

(b) The probability that a random sample of 13 time intervals between irruption has a mean longer than 84 minutes is 0.0526.

(c) The probability that a random sample of 20 time intervals between irruption has a mean longer than 84 minutes is 0.0222.

(d) The probability decreases because the variability in the sample mean decreases as we increase the sample size

(e) The population mean may be larger than 75 minutes between irruption.

Step-by-step explanation:

We are given that a geyser has a mean time between irruption of 75 minutes. Also, the interval of time between the eruption is normally distributed with a standard deviation of 20 minutes.

(a) Let X = the interval of time between the eruption

So, X ~ Normal([tex]\mu=75, \sigma^{2} =20[/tex])

The z-score probability distribution for the normal distribution is given by;

                            Z  =  [tex]\frac{X-\mu}{\sigma}[/tex]  ~ N(0,1)

where, [tex]\mu[/tex] = population mean time between irruption = 75 minutes

           [tex]\sigma[/tex] = standard deviation = 20 minutes

Now, the probability that a randomly selected Time interval between irruption is longer than 84 minutes is given by = P(X > 84 min)

    P(X > 84 min) = P( [tex]\frac{X-\mu}{\sigma}[/tex] > [tex]\frac{84-75}{20}[/tex] ) = P(Z > 0.45) = 1 - P(Z [tex]\leq[/tex] 0.45)

                                                        = 1 - 0.6736 = 0.3264

The above probability is calculated by looking at the value of x = 0.45 in the z table which has an area of 0.6736.

(b) Let [tex]\bar X[/tex] = sample time intervals between the eruption

The z-score probability distribution for the sample mean is given by;

                            Z  =  [tex]\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }[/tex]  ~ N(0,1)

where, [tex]\mu[/tex] = population mean time between irruption = 75 minutes

           [tex]\sigma[/tex] = standard deviation = 20 minutes

           n = sample of time intervals = 13

Now, the probability that a random sample of 13 time intervals between irruption has a mean longer than 84 minutes is given by = P([tex]\bar X[/tex] > 84 min)

    P([tex]\bar X[/tex] > 84 min) = P( [tex]\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }[/tex] > [tex]\frac{84-75}{\frac{20}{\sqrt{13} } }[/tex] ) = P(Z > 1.62) = 1 - P(Z [tex]\leq[/tex] 1.62)

                                                        = 1 - 0.9474 = 0.0526

The above probability is calculated by looking at the value of x = 1.62 in the z table which has an area of 0.9474.

(c) Let [tex]\bar X[/tex] = sample time intervals between the eruption

The z-score probability distribution for the sample mean is given by;

                            Z  =  [tex]\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }[/tex]  ~ N(0,1)

where, [tex]\mu[/tex] = population mean time between irruption = 75 minutes

           [tex]\sigma[/tex] = standard deviation = 20 minutes

           n = sample of time intervals = 20

Now, the probability that a random sample of 20 time intervals between irruption has a mean longer than 84 minutes is given by = P([tex]\bar X[/tex] > 84 min)

    P([tex]\bar X[/tex] > 84 min) = P( [tex]\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }[/tex] > [tex]\frac{84-75}{\frac{20}{\sqrt{20} } }[/tex] ) = P(Z > 2.01) = 1 - P(Z [tex]\leq[/tex] 2.01)

                                                        = 1 - 0.9778 = 0.0222

The above probability is calculated by looking at the value of x = 2.01 in the z table which has an area of 0.9778.

(d) When increasing the sample size, the probability decreases because the variability in the sample mean decreases as we increase the sample size which we can clearly see in part (b) and (c) of the question.

(e) Since it is clear that the probability that a random sample of 20 time intervals between irruption has a mean longer than 84 minutes is very slow(less than 5%0 which means that this is an unusual event. So, we can conclude that the population mean may be larger than 75 minutes between irruption.

Answer:

Quadrant II.

Step-by-step explanation:

Quadrant | has positive x and y coordinates.

Quadrant || has negative x and positive y coordinates.

Quadrant ||| has negative x and y coordinates.

Quadrant |V has positive x and negative y coordinates.

Since -3 is negative and 15 is positive, the answer is Quadrant II.

Answer:

90 degrees

Step-by-step explanation:

This question can be explained using the plan x and y axis.

Suppose you are moving from any positive point on x axis which can be considered Elm trail

let say point be (5,0).

Now you move at origin and

then take left turn,

your left turn at origin will be negative side of y axis(which can be considered Deer trail)

hence, you move on negative y axis.

Since we know that angle of intersection of x and y axis is 90 degrees.

Thus, angle measure of turn is 90 degrees.

Answer:

4. f(x) = 8x^4 – 3x + 5x^2​

Step-by-step explanation:

In choices 1., 2., and 3., each function is a 2nd degree function since the term with the highest degree has an exponent of 2 on x. In choice 4., the function is a 4th degree function since there is a term with x^4, and that is the highest exponent on x.

Answer: 4. f(x) = 8x^4 – 3x + 5x^2​

Answer:

Step-by-step explanation:

solve each inequality:

A : x+6<8  ,  x<-8-6 , x<-14

B: x+4≥-6 ,  x≥-10

C: x-3>-10 , x>-7

D:x≤-9

since -12 is on the left side of the number line then x≤ -9 would be the solution

Answer:

D. x+5<-4

Step-by-step explanation:

x+6<-8

x<-8-6

x<-14

x={-15,-16,-17...} No

x+4>-6

x>-6-4

x>-10

x={-10,-9,-8,-7...} No

x-3>-10

x>-10+3

x>7

x={8,9,10...} No

x+5<-4

x<-4-5

x<-9

x={-9,-10,-11,-12...} Yes.

Slope is the change in y over the change in x

Slope = (1-0) /( -3 - -4)

Slope = 1/1

Slope = 1

Answer:

Step-by-step explanation:

142(.07)= 9.94 amount of the sales tax

$142+9.94= $151.94

Answer:

B (48)

Step-by-step explanation:

One particular property of medians is the 2/3 ratio. Basically, the centroid separates the median into two line segments, and the longer line segment is 2/3 of the median length. So, 72 x 2/3 is 48.

Answer:

  20 minutes

Step-by-step explanation:

Melissa works as fast as two Bettys, so working together, they get the job done at the rate 3 Bettys could do it. That time is (60 minutes)/3 = 20 minutes.

Working together, Betty and Melissa can mow the lawn in 20 minutes.

_____

You can also think in terms of mowing rates as lawns per minute. The total mowing rate is ...

  Betty's rate + Melissa's rate = (1/60 lawns/min) +(1/30 lawns/min)

  = (1/60 +2/60) lawns/min = 1/20 lawns/min

The inverse rate is then ...

  20/1 min/lawn

Together, they take 20 minutes to mow 1 lawn.

Answer:

(A)Cost of Rental A, C= 15h

 Cost of Rental B, C=5h+50

 Cost of Rental C, C=9h+20

(B)

i. Rental C

ii. Rental A

iii. Rental B

Step-by-step explanation:

Let h be the number of hours for which the barbeque will be rented.

Rental A: $15/h

Rental B: $5/h + 50

Rental C: $9/h + 20

The graph of the three models is attached below

(b)11.05-4.30

When you keep the barbecue from 11.05 to 4.30 when the football match ends.

Number of Hours = 4.30 -11.05 =4 hours 25 Minutes = 4.42 Hours

Rental C should be chosen as it offers the lowest cost.

(c)11.05-12.30

Number of Hours = 12.30 -11.05 =1 hour 25 Minutes = 1.42 Hours

Rental A should be chosen as it offers the lowest cost.

(d)If the barbecue is returned the next day, say after 24 hours

Rental B should be chosen as it offers the lowest cost.

Answer:

I noticed a pattern:

3 * 2 + 6 = 12 and 2 * 2 + 5 = 9

This means that a*b = 2a + b.

Answer:

E. 6

Step-by-step explanation:

The y-intercept is where the graph crosses the y-axis when x = 0. In that case, simply plug in x as 0:

y = 2(0) + 6

y = 6

Therefore, our graph crosses the y-axis at 6.

Answer: 6

Step-by-step explanation: The equation of this line is written in slope-intercept form which is more commonly known as y = mx + b form.

In this form, the m or the coefficient of the x term represents the slope

of the line and the b or the constant term represents the y-intercept.

We can see that the y-intercept is 6.

Answer:

Mean

Step-by-step explanation:

-Mean is the average calculated by adding up all the prices and dividing them by the number of prices.

-Median is the middle value in the group of prices after they are organized from the lowest to the highest.

-Mode is the price that is repeated more frequently in the data set.

-SD refers to the quantity of variation between the prices.

-The range is the difference between the highest and the lowest price.

According to this, the answer is that the most option is the mean house price because it indicates the center of the values and it allows to get an overall idea of the prices which would allow you to have a clear view about the neighborhoods where you can shop for a home in.

The other options are not right because the median would indicate the middle value and the mode the most repeated value but they don't necessarily provide an exact image of the prices as for example, the most repeated value does not necessarily reflects the values of all the houses in the neighborhood. Also, SD calculates the variation and the range calculates the difference between prices which doesn't provide a clear picture about the neighborhoods where you can afford a house.

Answer:

1 = 95

2 = 77

3 = 85

4 = 103

Step-by-step explanation:

Inscribed angles are half their arc that their 2 lines intersect.

Answer:

[tex]t=\frac{50.857-51}{\frac{5.014}{\sqrt{7}}}=-0.075[/tex]    

The degrees of freedom are given by:

[tex]df=n-1=7-1=6[/tex]  

The p value for this case would be given:

[tex]p_v = 2*P(t_6 <-0.075)=0.943[/tex]

The p value for this case is lower than the significance level so then we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true mean is not significantly different from 51

Step-by-step explanation:

Info given

50, 53, 55, 43, 50, 47, 58.

We can calculate the sample mean and deviation with this formula:

[tex]\bar X=\frac{\sum_{i=1}^n X_i}{n}[/tex]

[tex]s=\sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2)}{n-1}}[/tex]

represent the mean height for the sample  

[tex]s=5.014[/tex] represent the sample standard deviation for the sample  

[tex]n=7[/tex] sample size  

represent the value that we want to test

[tex]\alpha=0.05[/tex] represent the significance level for the hypothesis test.  

t would represent the statistic (variable of interest)  

[tex]p_v[/tex] represent the p value

Hypothesis to test

We want to test if the true mean is equal to 51, the system of hypothesis would be:  

Null hypothesis:[tex]\mu = 51[/tex]  

Alternative hypothesis:[tex]\mu \neq 51[/tex]  

The statistic is given by:

[tex]t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}[/tex]  (1)  

Replacing we got:

[tex]t=\frac{50.857-51}{\frac{5.014}{\sqrt{7}}}=-0.075[/tex]    

The degrees of freedom are given by:

[tex]df=n-1=7-1=6[/tex]  

The p value for this case would be given:

[tex]p_v = 2*P(t_6 <-0.075)=0.943[/tex]

The p value for this case is lower than the significance level so then we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true mean is not significantly different from 51