1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
alekssr [168]
3 years ago
7

A rectangle has a length that is 12 ft longer

Mathematics
1 answer:
Reil [10]3 years ago
7 0
4x+24=84 4x=60 x=15 length =27 width = 15
You might be interested in
For her phone service , Rania pays a monthly fee of $ 18 , and an additional $0.06 per minute of use. The least she has been cha
pogonyaev

Answer:

I'm assuming we need to find the number of minute she as used. to do that we can right an inequality with m being the number of minutes

18+0.06m≥88.56

we then just solve this like we would with any other algebra equation, First we subtract 18 from both sides.

0.06m≥70.56

Then we dives by 0.06

m≥1176

Rania has used at least 1176 minutes

4 0
3 years ago
Someone help me with this ASAP!!!
frozen [14]
It is going to be 7.5
6 0
3 years ago
Read 2 more answers
An examination of the records for a random sample of 16 motor vehicles in a large fleet resulted in the sample mean operating co
levacccp [35]

Answer:

1. The 95% confidence interval would be given by (24.8190;27.8010)  

2. 4.7048 \leq \sigma^2 \leq 16.1961

3. t=\frac{26.31-25}{\frac{2.8}{\sqrt{16}}}=1.871    

t_{crit}=1.753

Since our calculated value it's higher than the critical value we have enough evidence at 5% of significance to reject th null hypothesis and conclude that the true mean is higher than 25 cents per mile.

4. t=(16-1) [\frac{2.8}{2.3}]^2 =22.2306

\chi^2 =24.9958

Since our calculated value is less than the critical value we don't hav enough evidence to reject the null hypothesis at the significance level provided.

Step-by-step explanation:

Previous concepts

\bar X=26.31 represent the sample mean for the sample  

\mu population mean (variable of interest)

s=2.8 represent the sample standard deviation

n=16 represent the sample size

Part 1

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

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

In order to calculate the critical value t_{\alpha/2} we need to find first the degrees of freedom, given by:

df=n-1=16-1=15

Since the Confidence is 0.95 or 95%, the value of \alpha=0.05 and \alpha/2 =0.025, and we can use excel, a calculator or a tabel to find the critical value. The excel command would be: "=-T.INV(0.025,15)".And we see that t_{\alpha/2}=2.13

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

26.31-2.13\frac{2.8}{\sqrt{16}}=24.819    

26.31+2.13\frac{2.8}{\sqrt{16}}=27.801

So on this case the 95% confidence interval would be given by (24.8190;27.8010)  

Part 2

The confidence interval for the population variance is given by the following formula:

\frac{(n-1)s^2}{\chi^2_{\alpha/2}} \leq \sigma^2 \leq \frac{(n-1)s^2}{\chi^2_{1-\alpha/2}}

The next step would be calculate the critical values. First we need to calculate the degrees of freedom given by:

df=n-1=16-1=15

Since the Confidence is 0.90 or 90%, the value of \alpha=0.1 and \alpha/2 =0.05, and we can use excel, a calculator or a table to find the critical values.  

The excel commands would be: "=CHISQ.INV(0.05,15)" "=CHISQ.INV(0.95,15)". so for this case the critical values are:

\chi^2_{\alpha/2}=24.996

\chi^2_{1- \alpha/2}=7.261

And replacing into the formula for the interval we got:

\frac{(15)(2.8)^2}{24.996} \leq \sigma^2 \leq \frac{(15)(2.8)^2}{7.261}

4.7048 \leq \sigma^2 \leq 16.1961

Part 3

We need to conduct a hypothesis in order to determine if actual mean operating cost is at most 25 cents per mile , the system of hypothesis would be:    

Null hypothesis:\mu \leq 25      

Alternative hypothesis:\mu > 25      

We don't know the population deviation, so for this case is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:      

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

Calculate the statistic      

We can replace in formula (1) the info given like this:      

t=\frac{26.31-25}{\frac{2.8}{\sqrt{16}}}=1.871    

Critical value  

On this case we need a critical value on th t distribution with 15 degrees of freedom that accumulates 0.05 of th area on the right and 0.95 of the area on the left. We can calculate this value with the following excel code:"=T.INV(0.95,15)" and we got t_{crit}=1.753

Conclusion      

Since our calculated valu it's higher than the critical value we have enough evidence at 5% of significance to reject th null hypothesis and conclude that the true mean is higher than 25 cents per mile.

Part 4

State the null and alternative hypothesis

On this case we want to check if the population standard deviation is more than 2.3, so the system of hypothesis are:

H0: \sigma \leq 2.3

H1: \sigma >2.3

In order to check the hypothesis we need to calculate the statistic given by the following formula:

t=(n-1) [\frac{s}{\sigma_o}]^2

This statistic have a Chi Square distribution distribution with n-1 degrees of freedom.

What is the value of your test statistic?

Now we have everything to replace into the formula for the statistic and we got:

t=(16-1) [\frac{2.8}{2.3}]^2 =22.2306

What is the critical value for the test statistic at an α = 0.05 significance level?

Since is a right tailed test the critical zone it's on the right tail of the distribution. On this case we need a quantile on the chi square distribution with 15 degrees of freedom that accumulates 0.05 of the area on the right tail and 0.95 on the left tail.  

We can calculate the critical value in excel with the following code: "=CHISQ.INV(0.95,15)". And our critical value would be \chi^2 =24.9958

Since our calculated value is less than the critical value we FAIL to reject the null hypothesis.

7 0
3 years ago
What do you think x equals?
Korvikt [17]
X is the line across the graph. Or in other word the answer to a problem
3 0
3 years ago
Read 2 more answers
Given the domain {-2, 1,5}, what is the range for the relation 4x +y = 3?
Simora [160]

Answer: (11, -1, -17)

Step-by-step explanation:

4x+y=3

4(-2)+y=3

-8+y=3

y=3+8

y=11

4x+y=3

4.1+y=3

4+y=3

y=3-4

y=-1

4x+y=3

4.5+y=3

20+y=3

y=3-20

y= -17

3 0
3 years ago
Other questions:
  • A high-speed train travels 480 km from Paris to Grenoble, France, at an average speed of 180 km/h. How long will it take the tra
    14·1 answer
  • Janice bought her mother a bunch of 10 flowers. Two of the flowers are daisies. One half of the remaining flowers are tulips. Wr
    12·2 answers
  • Three students scheduled interviews for summer employment at the Brookwood Institute. In each case the interview results in eith
    14·1 answer
  • The line of symmetry of the parabola whose equation is y = ax^2 -4x + 3 is
    6·1 answer
  • How many cups of flour are needed to make 3 dozens of dinner rolls
    10·1 answer
  • I don't understand this Geometry question. Can someone help, please?
    11·1 answer
  • Please help asap I give brainliest,
    5·1 answer
  • Geometry help don’t take points if I get 70%+ I’ll give some away!!
    14·1 answer
  • If you add 50 million and you divide by the power of ten what do you get
    6·2 answers
  • Please help me, look at the picture I need help... please ​
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!