Please help me as soon as possible

Answer:

26.59 minutes

Step-by-step explanation:

Let's say the time needed to do the driveway combined is x. Sue does y parts of the driveway, and Tom does z parts of the driveway. Combined, y + z = 100% = 1, as they finish the whole driveway.

Next, Tom will take 45 * z minutes to do his part of the driveway. For example, if he did 50% = 0.5 of the driveway, he would take 45 * 0.5 = 22.5 minutes to do it. Similarly, Sue will take 65 *y minutes to do her part of the driveway. Since they will finish at the same time, we can say

45 * z = 65 * y

y + z = 1

Therefore, if we subtract y from both sides of the second equation, we have

z = 1-y

We can then plug 1-y in for z in the first equation to get

45 * (1-y) = 65 * y

45 - 45*y = 65*y

add both sides by 45 * y to separate the y values and their coefficients

45 = 110 * y

divide both sides by 110 to find y

y = 45/110 = 0.409

Use 1-y=z to get z = 1-0.409 = 0.59

Therefore, 45*z = 26.59 = 65*y

Answer:

(1) +t+=+1.2+ hrs

Step-by-step explanation:

Step-by-step explanation:

You can simply plot these points on a graph and see where the line goes. It go

Step-by-step explanation:

she gives each of her children $25 each,if Raul spends $15 then he would have $10 left.

Division then subtraction can be used to solve the problem.

An expression in mathematics is made up of numbers, variables, and functions (such as addition, subtraction, multiplication or division etc.) You can think of expressions as being comparable to phrases.

Given

she gives each of her children $25 each,if Raul spends $15 then he would have $10 left.

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Answer:

A

Step-by-step explanation:

small dog eats 3/4 cup each day

large dog eats 1 cup each day

~after 1 week (x7)~

small dog = 5.25 cups

large dog = 7 cups

(7-5.25=1.75)

= therefore 1 and 3/4 cups

Answer:

The mean of the sampling distribution is always equal to the mean of the population.

The mean of the sampling distribution of the sample mean is 45.

Given that,

Based on the above information, the calculation is as follows:

= mean of the random variable X

= 45

As the sampling distribution mean should always be equivalent to the population mean.

Therefore we can conclude that the mean of the sampling distribution of the sample mean is 45.

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Answer:

f(-1) = 1

f(0) = 20

f(2) = 38

Step-by-step explanation:

f(-1) = 9×-1 + 10 = -9 + 10 = 1

f(0) = 9×0 + 20 = 0 + 20 = 20

f(2) = 9×2 + 20 = 18 + 20 = 38

we needed to use the second definition for f(0), because that is the same as saying x=0.

and that is in the domain of the second function definition ( x>=0).

Answer:

?

Step-by-step explanation:

Answer:

The answer is true

Step-by-step explanation:

Answer:

x = -1 and y = 1

Step-by-step explanation:

5x + 2y = -3 . . . . . . . (i)

x + 5y = 4 . . . . . . . (ii)

x + 5y = 4

x = 4 - 5y

5(4 - 5y) + 2y = -3

20 - 25y + 2y = -3

-23y = - 23

y = 1

5x + 2(1) = -3

5x + 2 = -3

5x = - 5

x = -1

Answer:

0.7671 = 76.71% probability that he was taught by method A

Step-by-step explanation:

Conditional Probability

We use the conditional probability formula to solve this question. It is

[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]

In which

P(B|A) is the probability of event B happening, given that A happened.

[tex]P(A \cap B)[/tex] is the probability of both A and B happening.

P(A) is the probability of A happening.

In this question:

Event A: Person learned Spanish successfully.

Event B: Method A was used.

Probability of a person learning Spanish successfully:

70% of 80%(using method A)

85% of 20%(using method B)

So

[tex]P(A) = 0.7*0.8 + 0.85*0.2 = 0.73[/tex]

Probability of a person learning Spanish successfully and using method A:

70% of 80%, so:

[tex]P(A \cap B) = 0.7*0.8 = 0.56[/tex]

What is the probability that he was taught by method A?

[tex]P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.56}{0.73} = 0.7671[/tex]

0.7671 = 76.71% probability that he was taught by method A

Answer:

You would expect 807 babies  to weigh between 3 and 6 pounds.

Step-by-step explanation:

We are given that

Mean,[tex]\mu=5.4[/tex]pounds

Standard deviation,[tex]\sigma=1.8[/tex]pounds

n=1500

We have to find how  many would you expect to weigh between 3 and 6 pounds.

The weights for newborn babies is approximately normally distributed.

Now,

[tex]P(3<x<6)=P(\frac{3-5.4}{1.8}<\frac{x-\mu}{\sigma}<\frac{6-5.4}{1.8})[/tex]

[tex]=P(-1.33<Z<0.33)[/tex]

[tex]P(3<x<6)=P(Z<0.33)-P(Z<-1.33)[/tex]

[tex]P(3<x<6)=0.62930-0.09176[/tex]

[tex]P(3<x<6)=0.538[/tex]

Number of newborn  babies expect to weigh between 3 and 6 pounds

=[tex]1500\times 0.538=807[/tex]

Answer:

nine 9 classes in the histogram

Answer:

Just A and C

Step-by-step explanation:

B doesn't count because you would not be looking at the 9. Only the 4.

You only look at one number to the right.

Answer:

A and C are correct, but not B

Step-by-step explanation:

When you round, you only look at the number behind the place you are rounding.

6.04 doesn't round to 6.1, so that is not correct

Answer:

Option A. -1/20x

Step-by-step explanation:

[tex] \frac{5x + 1}{5x} - \frac{4x + 1}{4x} [/tex]

[tex] = \frac{20x + 4x - 20x - 5x}{20x^{2} } [/tex]

[tex] = \frac{ - x}{20x^{2} } [/tex]

[tex] - \frac{1}{20x} [/tex]

Answered by GAUTHMATH

Answer:

[tex]B = \frac{3V}{h}[/tex]

Step-by-step explanation:

Given

[tex]V = \frac{1}{3}Bh[/tex]

Required

Solve for B

We have;

[tex]V = \frac{1}{3}Bh[/tex]

Multiply by 3

[tex]3V = Bh[/tex]

Make B the subject

[tex]B = \frac{3V}{h}[/tex]

Answer:

tgis moght help

Step-by-step explanation:

https://opentextbc.ca/introbusinessstatopenstax/chapter/full-hypothesis-test-examples/

the SAS similarity theorem

Answer:

Step-by-step explanation:

I  might be wrong but it 1900 in merchandise

The clerk earned a total of $770 for the month she sold $8000 in merchandise.

To calculate the clerk's earnings for the month she sold $8000 in merchandise, we need to consider her monthly salary and commission.

The clerk's monthly salary is $500, which is a fixed amount.

For the commission, we need to calculate the sales amount that exceeds $3500. In this case, the sales amount exceeding $3500 is $8000 - $3500 = $4500.

The commission is calculated as 6% of the sales amount exceeding $3500. Therefore, the commission earned by the clerk is 6% of $4500.

Commission = 6/100 * $4500

Commission = $270

Adding the monthly salary and commission, we can calculate the clerk's total earnings for the month:

Total earnings = Monthly salary + Commission

Total earnings = $500 + $270

Total earnings = $770

Therefore, the clerk earned a total of $770 for the month she sold $8000 in merchandise.

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Answer:

5

Step-by-step explanation:

Given :

To Find :

Solution:

Put on the respective values ,

⇒ 4b - y = 4 × 3 - 7

⇒ 4b - y = 12 - 7

⇒ 4b - y = 5

Hence the required answer is 5 .

Answer: 5

Step-by-step explanation:

We can plug in the numbers for variables. So, our new equation would becomes 4x3-7. We first evaluate 4x3=12. Then, 12-7=5. Hence, your answer is 5.

Answer:

a. $10  

b. 10.46  

c. 10.46  

d. 0.096

Answer:

The 90% confidence interval to estimate the average difference in scores between the two courses is (-1.088, 20.252).

Step-by-step explanation:

We have the standard deviation for the differences, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 8 - 1 = 7

90% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 7 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.9}{2} = 0.95[/tex]. So we have T = 1.8946

The margin of error is:

[tex]M = T\frac{s}{\sqrt{n}} = 1.8946\frac{15.9274}{\sqrt{8}} = 10.67[/tex]

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 9.582 - 10.67 = -1.088

The upper end of the interval is the sample mean added to M. So it is 9.582 + 10.67 = 20.252

The 90% confidence interval to estimate the average difference in scores between the two courses is (-1.088, 20.252).

Answer: (3, -3)

Step-by-step explanation:

You substitute each point into the function and see if it fits:

(-2, -1) ⇒ -2(-2) + 3 = 4 + 3 = 7 ≠ -1

(3, -3) ⇒ -2(3) + 3 = -6 + 3 = -3

(3, 3) ⇒ -2(3) + 3 = -6 + 3 = -3 ≠ 3

(-3, -9) ⇒ -2(-3) + 3 = 6 + 3 = 9 ≠ -9

Answer:

Step-by-step explanation:

As shown in the graph,

A, B, C and D are the vertices of a square, all sides of the square will be equal in measure.

Coordinates of A → (0, 0)

Coordinates of B → (0, m)

Distance between point D and point A = m

Therefore, coordinates of point D → (m, 0)

Now point C will be equally distant from the points B and D.

Coordinates of C → (m, m)

Answer:

The angle between them is 60 degrees

Step-by-step explanation:

Given

[tex]a = 2i + j -3k[/tex]

[tex]b = 3i - 2j -k[/tex]

Required

The angle between them

The cosine of the angle between them is:

[tex]\cos(\theta) = \frac{a\cdot b}{|a|\cdot |b|}[/tex]

First, calculate a.b

[tex]a \cdot b =(2i + j -3k) \cdot (3i - 2j -k)[/tex]

Multiply the coefficients of like terms

[tex]a \cdot b =2 * 3 - 1 * 2 - 3 * -1[/tex]

[tex]a \cdot b =7[/tex]

Next, calculate |a| and |b|

[tex]|a| = \sqrt{2^2 + 1^2 + (-3)^2[/tex]

[tex]|a| = \sqrt{14[/tex]

[tex]|b| = \sqrt{3^2 + (-2)^2 + (-1)^2}[/tex]

[tex]|b| = \sqrt{14}[/tex]

Recall that:

[tex]\cos(\theta) = \frac{a\cdot b}{|a|\cdot |b|}[/tex]

This gives:

[tex]\cos(\theta) = \frac{7}{\sqrt{14} * \sqrt{14}}[/tex]

[tex]\cos(\theta) = \frac{7}{14}[/tex]

[tex]\cos(\theta) = 0.5[/tex]

Take arccos of both sides

[tex]\theta =\cos^{-1}(0.5)[/tex]

[tex]\theta =60^o[/tex]

Answer:

C

Step-by-step explanation:

200 x 5 = 1,000

100 x 10 = 1,000

C - 5 to 10 days

Answer:

C. 5 to 10 days

Step-by-step explanation:

If she drove 100 miles per day, then

1000/100 = 10

it took her 10 days.

If she drove 200 miles per day, then

1000/200 = 5

it took her 5 days.

Since she drove between 100 miles and 200 miles per days,

it took her from 5 to 10 days.

Answer: C. 5 to 10 days

Answer:

The critical value that should be used in constructing the confidence interval is T = 1.316.

The 80% confidence interval for the mean waste recycled per person per day for the population of Montana is between 2.741 pounds and 2.859 pounds.

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 26 - 1 = 25

80% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 25 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.8}{2} = 0.9[/tex]. So we have T = 1.316

The critical value that should be used in constructing the confidence interval is T = 1.316.

The margin of error is:

[tex]M = T\frac{s}{\sqrt{n}} = 1.316\frac{0.23}{\sqrt{26}} = 0.059[/tex]

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 2.8 - 0.059 = 2.741 pounds

The upper end of the interval is the sample mean added to M. So it is 2.8 + 0.059 = 2.859 pounds.

The 80% confidence interval for the mean waste recycled per person per day for the population of Montana is between 2.741 pounds and 2.859 pounds.

Answer:

.0668

Step-by-step explanation:

Formula:

z=(x-average)/standard deviation

(2.5-2.8)/.2= -1.5

Go to a ztable and find the value for 1.5  (.9332) and take the compliment of this (we can do this because the normal distribution is symmetrical)

1-.9332= .0668