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
Elanso [62]
3 years ago
5

I'll give points and brainalist for answer / explanation

Mathematics
1 answer:
Valentin [98]3 years ago
5 0

Answer:

D. 8

Step-by-step explanation:

C= 2πr

π= 3.14

C= 25.12

25.12 = 2 * 3.14 * r

r= 4

d= 2r

d= 8

You might be interested in
PLEASE HELP!!! WILL MARK BRAINLIEST!!! Answers only related to the question please!
Margarita [4]

Answer:

x is form

Step-by-step explanation:

6 0
3 years ago
The table below shows the radius y, in inches, created by growing algae in x days: Time (x) (days) 1 4 7 10 Radius (y) (inches)
tatuchka [14]
PART A:
Given the table below showing the radius y, in inches, created by growing algae in x days.

Time (x) (days):          1       4        7        10
Radius (y) (inches):    1       8       11       12

We can find the find the correlation coeficient of the data using the table below:
\begin{center}
\begin{tabular}
{|c|c|c|c|c|}
x & y & x^2 & y^2 & xy \\ [1ex]
1 & 1 & 1 & 1 & 1\\
4 & 8 & 16 & 64 & 32\\
7 & 11 & 49 & 121 & 77\\
10 & 12 & 100 & 144 & 120\\ [1ex]
\Sigma x=22 & \Sigma y=32 & \Sigma x^2=166 & \Sigma y^2=330 & \Sigma xy=230
\end{tabular}
\end{center}

Recall that the correlation coefitient is given by the equation:
r= \frac{n(\Sigma xy)-(\Sigma x)(\Sigma y)}{ \sqrt{(n\Sigma x^2-(\Sigma x)^2)(n\Sigma y^2-(\Sigma y)^2)} }  \\  \\ = \frac{4(230)-(22)(32)}{ \sqrt{(4(166)-(22)^2)(4(330)-(32)^2)} } = \frac{920-704}{ \sqrt{(664-484)(1,320-1,024)}}  \\  \\ = \frac{216}{ \sqrt{180(296)}} = \frac{216}{ \sqrt{53,280} } = \frac{216}{230.8} =0.94

[Notice: even without using the formular to find the value of the correlation coeficient, it can be seen that the value of y strictly increases as the valu of x increases. This means that the value of the correlation coeficient is closer to +1 and from the options the value that is closest to +1 is 0.94]

From the value of the correlation coeffeicient, it can be deduced that the radius of the algae has a strong positive relationship with the time.

Recall the for the value of the correlation coeficient closer to +1, the relationship is strong positive, for the value closer to -1, the value is strong negative and for the values closer to zero, either way of zero is a weak positive if it is positive and weak negative if it is negative.


PART B:
Recall that the slope of a straight line passing through two points
(x_1,y_1) and (x_2,y_2)
is given by
m= \frac{y_2-y_1}{x_2-x_1}

Thus the slope of the graph of radius versus time between 4 and 7 days, [i.e. the line passes through points (4, 8) and (7, 11)] is given by
m= \frac{11-8}{7-4}= \frac{3}{3} =1

The value of the slope means that the radius of the algea grows by 1 inch evry day between day 4 and day 7.


PART C:
We can say that the data above represent both correlation and causationg.

Recall that correlation expresses the relationship between two variables while causation expresses that an event is as a result of another event.

From the information above, we have seen that there is a relationship (correlation) between the passing of days and the growth in the radius of the algae.

Also we can conclude that the growth in the radius of algae is a function of the passing of days, i.e. the growth in the radius of algae is as a result of the passing of days.

Therefore, <span>the data in the table represent both correlation and causation.</span>
6 0
3 years ago
What is 5/12 of 2/5 i need help
Marianna [84]

Answer:10/60

If need to  simply it is 1/6.

Step-by-step explanation: Mutiply 5/12 by 2/5 .

5 0
3 years ago
What type of number is 0? Rational, Irrational, Whole number, Integer
gladu [14]
It is a whole number and integer.
4 0
4 years ago
Read 2 more answers
Cynthia purchase 3 video games from the sales bin that were each the same price. She also bought 2 DVDs for $15 each. Cynthia sp
mr Goodwill [35]
Twenty nine dollars for each game. I added both dvds. 15 plus 15 is 30. then subtracted it by the total price, than got 87. I divided by 3 and got 29
5 0
4 years ago
Other questions:
  • A triangle with the two biggest sides are 8in what is the third side
    10·1 answer
  • Nate borrowed $400 to pay for car repairs. If he agreed to repay the loan at simple annual interest rate of 6%, how much interes
    7·1 answer
  • A $10,000 loan is to be repaid with 7 equal half-yearly instalments, the first repayment being in
    15·1 answer
  • UESTION 2 If you get on a plane in New York City at 9 a.m. and fly 6 hours to San Francisco, what time will the clocks read in S
    13·1 answer
  • Please help with this question!!!!!
    15·1 answer
  • A spinner with 4 equal sections (red, blue, green, yellow) is spun 43 times. About how many times would you predict it lands on
    12·1 answer
  • 2x + y = 20<br> 6x – 5 y= 12
    10·2 answers
  • A high speed train travels a distance of 503 km in 3 hours.
    9·1 answer
  • Find the quotient.<br><br> −2 1/2 ÷ 3/4
    8·2 answers
  • <img src="https://tex.z-dn.net/?f=%20%5Cboxed%7B%5Cboxed%7B%20%5Cbegin%7Barray%7D%7B%7D%5Clarge%5Ctt%20The%20%20%5C%5C%20%20%5Ct
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!