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
Alecsey [184]
3 years ago
12

Help me with this question

Mathematics
1 answer:
lys-0071 [83]3 years ago
7 0

Answer:

4π or about 12.56

Step-by-step explanation:

The circumference of a circle is calculated with diameter so we first need to find the diameter. Going from radius to diameter can be done by multiplying by 2, therefore 2*2=4 so the diameter is 4.

Now that we have the diameter we need to use the formula for circumference which is c=4*π. Because the question doesn't state to use 3.14 to multiply then you would usually use 4π as your answer but if you were to use 3.14 then you would get a circumference of 4*3.14=12.56.

You might be interested in
PLS HELP ME QUICK what is the answer image below
soldi70 [24.7K]

Answer:

22

Step-by-step explanation:

3 0
3 years ago
How much time should be allowed for a 392-km car trip if the car will be traveling at 120km/h
Diano4ka-milaya [45]

Answer:3hrs 16min

Step-by-step explanation:

392/120 = 49/15 hours = 3 hours + 4/15 hours = 3 hours + 4/15 x 60 min = 3 hours + 16 min

5 0
2 years ago
Is √8 a rational number ?
bonufazy [111]
Yeah I’m pretty sure it is a rational number
4 0
2 years ago
Read 2 more answers
Please help me thank you
gayaneshka [121]

Answer:

x = 6

Step-by-step explanation:

First, separate the problem into -\frac{2x}{3} +9=\frac{4x}{3} - 3

Then, Subtract 9 from both sides of the equation. -\frac{2x}{3} +9-9=\frac{4}{3} * x - 3-9

Simplify. -\frac{2x}{3}=\frac{4x}{3}-12

Multiply 3 to each side, which will give you -2x = 4x - 36

Subtract 4x from each side  -2x - 4x = 4x - 36x - 4x

Combine like terms: -6x = -36

Divide both sides by -6

Your answer should be 6

<em>(sorry for the late answer)</em>

5 0
3 years ago
A sample of 200 observations from the first population indicated that x1 is 170. A sample of 150 observations from the second po
igor_vitrenko [27]

Answer:

a) For this case the value of the significanceis \alpha=0.05 and \alpha/2 =0.025, we need a value on the normal standard distribution thataccumulates 0.025 of the area on each tail and we got:

z_{\alpha/2} =1.96

If the calculated statistic |z_{calc}| >1.96 we can reject the null hypothesis at 5% of significance

b) Where \hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{170+110}{200+150}=0.8  

c)z=\frac{0.85-0.733}{\sqrt{0.8(1-0.8)(\frac{1}{200}+\frac{1}{150})}}=2.708    

d) Since the calculated value satisfy this condition 2.708>1.96 we have enough evidence at 5% of significance that we have a significant difference between the two proportions analyzed.

Step-by-step explanation:

Data given and notation    

X_{1}=170 represent the number of people with the characteristic 1

X_{2}=110 represent the number of people with the characteristic 2  

n_{1}=200 sample 1 selected  

n_{2}=150 sample 2 selected  

p_{1}=\frac{170}{200}=0.85 represent the proportion estimated for the sample 1  

p_{2}=\frac{110}{150}=0.733 represent the proportion estimated for the sample 2  

\hat p represent the pooled estimate of p

z would represent the statistic (variable of interest)    

p_v represent the value for the test (variable of interest)  

\alpha=0.05 significance level given  

Concepts and formulas to use    

We need to conduct a hypothesis in order to check if is there is a difference between the two proportions, the system of hypothesis would be:    

Null hypothesis:p_{1} = p_{2}    

Alternative hypothesis:p_{1} \neq p_{2}    

We need to apply a z test to compare proportions, and the statistic is given by:    

z=\frac{p_{1}-p_{2}}{\sqrt{\hat p (1-\hat p)(\frac{1}{n_{1}}+\frac{1}{n_{2}})}}   (1)  

a.State the decision rule.

For this case the value of the significanceis \alpha=0.05 and \alpha/2 =0.025, we need a value on the normal standard distribution thataccumulates 0.025 of the area on each tail and we got:

z_{\alpha/2} =1.96

If the calculated statistic |z_{calc}| >1.96 we can reject the null hypothesis at 5% of significance

b. Compute the pooled proportion.

Where \hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{170+110}{200+150}=0.8  

c. Compute the value of the test statistic.                                                                                              

z-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.    

Replacing in formula (1) the values obtained we got this:    

z=\frac{0.85-0.733}{\sqrt{0.8(1-0.8)(\frac{1}{200}+\frac{1}{150})}}=2.708    

d. What is your decision regarding the null hypothesis?

Since the calculated value satisfy this condition 2.708>1.96 we have enough evidence at 5% of significance that we have a significant difference between the two proportions analyzed.

5 0
3 years ago
Other questions:
  • I need help ASAP! PLEASEEEE ​
    6·1 answer
  • What is the slope of a line that is perpendicular to the line whose equation is 5y+2x=12?
    10·1 answer
  • URGENT!! A 16 inch board is to be cut into three pieces so that the second piece is twice as long as the first piece and the thi
    15·2 answers
  • What is the measure of angle ACE shown in the diagram below? 180° and 30°
    10·1 answer
  • What is r the common ration in the geometic sequence 2, -14, 98, -687
    12·1 answer
  • Help!! i don't understand either of these :(
    8·1 answer
  • What is the [?]
    12·1 answer
  • Find the volume. Show your work. Please help if you don’t know the answer dw
    15·1 answer
  • Avery walks 2.5 miles each day. One day a week he only walks 1.2 miles those days. What is the total amount he would walk in 15
    8·1 answer
  • Determine the domain and range of (g ○ f)(x) if f of x is equal to 4 over the quantity x squared minus 4 end quantity and g(x) =
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!