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
Sedbober [7]
3 years ago
15

What is 2+5, please hurry i can't figure it out and my test is about to end

Mathematics
2 answers:
Vesna [10]3 years ago
6 0

Answer:

7

Step-by-step explanation:

2+5=7

erastova [34]3 years ago
3 0

Answer:

7

Step-by-step explanation:

2+5=7

You might be interested in
I am thinking of a number when I double my number and then subtract the resulting from I get -1 what is my number
igor_vitrenko [27]

Answer: 1

Step-by-step explanation:

-1 + 2 = 1 ????

4 0
3 years ago
Please answer this i'll give brainliest
solong [7]

Answer:

It is B you are correct

Step-by-step explanation:

4 0
3 years ago
Read 2 more answers
Chad is studying transformations. He starts with quadrilateral ABCD.
denis23 [38]

Answer:

(5, -9)

Step-by-step explanation:

7 0
3 years ago
Read 2 more answers
4. Which of the following is the equation of a line that is perpendicular to a line that
IrinaK [193]

Answer:

C. y = 1/4 x - 3

Step-by-step explanation:

6 0
2 years ago
A wheat farmer cuts down the stalks of wheat and gathers them in 200 piles. The 200 gathered piles will be put on a truck. The t
denpristay [2]

Answer:

Check the explanation

Step-by-step explanation:

We want to estimate the total weight of grain on the field based on the data on a simple random sample of 5 piles out of 200. The population and sample sizes are N=200 & n=5 respectively.

1) Let Y_1,Y_2,...,Y_{200} be the weight of grain in the 200 piles and y_1,y_2,...,y_{5} be the weights of grain in the pile from the simple random sample.

We know, the sample mean is an unbiased estimator of the population mean. Therefore,

\widehat{\mu}=\overline{y}=\frac{1}{5}\sum_{i=1}^{5}y_i=\frac{1}{5}(3.3+4.1+4.7+5.9+4.5)=4.5

where \mu is the mean weight of grain for all the 200 piles.

Hence, the total grain weight of the population is

\widehat{Y}=Y_1+Y_2+...+Y_{200}

=200\times \widehat{\mu}\: \: \: =200\times 4.5\: \: \: =900\, lbs

2) To calculate a bound on the error of estimates, we need to find the sample standard deviation.

The sample standard deviation is

 S=\sqrt{\frac{1}{5-1}\sum_{i=1}^{5}(y_i-\overline{y})^2}\: \: \: =0.9486

Then, the standard error of \widehat{Y} is

\sigma_{\widehat{Y}} =\sqrt{\frac{N^2S^2}{n}\bigg(\frac{N-n}{N}\bigg)}\: \: \:=83.785

Hence, a 95% bound on the error of estimates is

[\pm z_{0.025}\times \sigma_{\widehat{Y}}]\: \: \: =[\pm 1.96\times 83.875]\: \: \: =[\pm 164.395]

3) Let x_1,x_2,...,x_5 denotes the total weight of the sampled piles.

Mean total weight of the sampled piles is

\overline{x}=\frac{1}{5}\sum_{i=1}^{5}x_i=45

The sample ratio is

r=\frac{\overline{y}}{\overline{x}}=\frac{4.5}{45}=0.1 , this is also the estimate of the population ratio R=\frac{\overline{Y}}{\overline{X}} .

Therefore, the estimated total weight of grain in the population using ratio estimator is

\widehat{Y}_R\: \: =r\times 8800\: \: =0.1\times 8800\: \: =880\, lbs

4) The variance of the ratio estimator is

var(r)=\frac{N-n}{N}\frac{1}{n}\frac{1}{\mu_x^2}\frac{\sum_{i=1}^{5}(y_i-rx_i)^2}{n-1}   , where \mu_x=8800/200=44lbs

=\frac{200-5}{200}\, \frac{1}{5}\: \frac{1}{44^2}\, \frac{0.2}{5-1}=0.000005

Hence, the standard error of the estimate of the total population is

\sigma_R=\sqrt{X^2 \: var(r)}\: \: \: =\sqrt{8800^2\times 0.000005}\: \: \:=21.556

Hence, a 95% bound on the error of estimates is

[\pm z_{0.025}\times \sigma_{R}]\: \: \: =[\pm 1.96\times 21.556]\: \: \: =[\pm 42.25]

8 0
4 years ago
Read 2 more answers
Other questions:
  • At the party, 6/16 of the guest were playing games and 3/8 of the guest were singing.Pat said that the number of guest were play
    15·2 answers
  • The cost to rent a dump truck is $50 per day plus $26 per hour of use. What is the maximum number of hours the truck can be used
    6·1 answer
  • An angle that is greater than 90 degrees<br> is called a _______.
    6·2 answers
  • Marcus walks 1.45 km to the store. Levon walks 2.1 times the distance that Marcus walks to meet at the store. How far does Levon
    10·1 answer
  • A rectangular fish pond is 21 ft2 in area. If the owner can surround the pond with a 20-foot fence, what are the dimensions of t
    10·1 answer
  • *PLEASE ANSWER* What is the value of d if the volume of Prism f is 99 cubic units?
    7·1 answer
  • can we prove LMN is congruent to XYZ ? if so, witch postulate can we use to do so ? if not , explain why.
    10·1 answer
  • Find the distance between each pair of points in the coordinate plane.
    13·1 answer
  • Compute the distance between the two points. (5, –2) and (–8, –3)
    11·2 answers
  • The points (–7, 7) and (6, –6) fall on a particular line. What is its equation in slope-intercept form?
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!