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Refer to the [link] . Find the third quartile. What is another name for the third quartile?

The third quartile is the 75 th percentile, which is four. The 65 th percentile is between three and four, and the 90 th percentile is between four and 5.75. The third quartile is between 65 and 90, so it must be four.

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Collaborative statistics

Your instructor or a member of the class will ask everyone in class how many sweaters they own. Answer the following questions:

  1. How many students were surveyed?
  2. What kind of sampling did you do?
  3. Construct two different histograms. For each, starting value = _____ ending value = ____.
  4. Find the median, first quartile, and third quartile.
  5. Construct a table of the data to find the following:
    1. the 10 th percentile
    2. the 70 th percentile
    3. the percent of students who own less than four sweaters

A formula for finding the k Th percentile

If you were to do a little research, you would find several formulas for calculating the k th percentile. Here is one of them.

k = the k th percentile. It may or may not be part of the data.

i = the index (ranking or position of a data value)

n = the total number of data

  • Order the data from smallest to largest.
  • Calculate i = k 100 ( n + 1 )
  • If i is an integer, then the k th percentile is the data value in the i th position in the ordered set of data.
  • If i is not an integer, then round i up and round i down to the nearest integers. Average the two data values in these two positions in the ordered data set. This is easier to understand in an example.

Listed are 29 ages for Academy Award winning best actors in order from smallest to largest.
18; 21; 22; 25; 26; 27; 29; 30; 31; 33; 36; 37; 41; 42; 47; 52; 55; 57; 58; 62; 64; 67; 69; 71; 72; 73; 74; 76; 77

  1. Find the 70 th percentile.
  2. Find the 83 rd percentile.
    • k = 70
    • i = the index
    • n = 29
    i = k 100 ( n + 1) = ( 70 100 )(29 + 1) = 21. Twenty-one is an integer, and the data value in the 21 st position in the ordered data set is 64. The 70 th percentile is 64 years.
    • k = 83 rd percentile
    • i = the index
    • n = 29
    i  = k 100 ( n + 1) = ) 83 100 )(29 + 1) = 24.9, which is NOT an integer. Round it down to 24 and up to 25. The age in the 24 th position is 71 and the age in the 25 th position is 72. Average 71 and 72. The 83 rd percentile is 71.5 years.
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Try it

Listed are 29 ages for Academy Award winning best actors in order from smallest to largest.

18; 21; 22; 25; 26; 27; 29; 30; 31; 33; 36; 37; 41; 42; 47; 52; 55; 57; 58; 62; 64; 67; 69; 71; 72; 73; 74; 76; 77
Calculate the 20 th percentile and the 55 th percentile.

k = 20. Index = i = k 100 ( n + 1 ) = 20 100 (29 + 1) = 6. The age in the sixth position is 27. The 20 th percentile is 27 years.

k = 55. Index = i = k 100 ( n + 1 ) = 55 100 (29 + 1) = 16.5. Round down to 16 and up to 17. The age in the 16 th position is 52 and the age in the 17 th position is 55. The average of 52 and 55 is 53.5. The 55 th percentile is 53.5 years.

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Note

You can calculate percentiles using calculators and computers. There are a variety of online calculators.

A formula for finding the percentile of a value in a data set

  • Order the data from smallest to largest.
  • x = the number of data values counting from the bottom of the data list up to but not including the data value for which you want to find the percentile.
  • y = the number of data values equal to the data value for which you want to find the percentile.
  • n = the total number of data.
  • Calculate x + 0.5 y n (100). Then round to the nearest integer.

Questions & Answers

Three charges q_{1}=+3\mu C, q_{2}=+6\mu C and q_{3}=+8\mu C are located at (2,0)m (0,0)m and (0,3) coordinates respectively. Find the magnitude and direction acted upon q_{2} by the two other charges.Draw the correct graphical illustration of the problem above showing the direction of all forces.
Kate Reply
To solve this problem, we need to first find the net force acting on charge q_{2}. The magnitude of the force exerted by q_{1} on q_{2} is given by F=\frac{kq_{1}q_{2}}{r^{2}} where k is the Coulomb constant, q_{1} and q_{2} are the charges of the particles, and r is the distance between them.
Muhammed
What is the direction and net electric force on q_{1}= 5µC located at (0,4)r due to charges q_{2}=7mu located at (0,0)m and q_{3}=3\mu C located at (4,0)m?
Kate Reply
what is the change in momentum of a body?
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what is a capacitor?
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Capacitor is a separation of opposite charges using an insulator of very small dimension between them. Capacitor is used for allowing an AC (alternating current) to pass while a DC (direct current) is blocked.
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please solve
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8m/s²
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What is Thermodynamics
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velocity can be 72 km/h in question. 72 km/h=20 m/s, v^2=2.a.x , 20^2=2.a.50, a=4 m/s^2.
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A boat travels due east at a speed of 40meter per seconds across a river flowing due south at 30meter per seconds. what is the resultant speed of the boat
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Someone
which has a higher temperature, 1cup of boiling water or 1teapot of boiling water which can transfer more heat 1cup of boiling water or 1 teapot of boiling water explain your . answer
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I believe temperature being an intensive property does not change for any amount of boiling water whereas heat being an extensive property changes with amount/size of the system.
Someone
Scratch that
Someone
temperature for any amount of water to boil at ntp is 100⁰C (it is a state function and and intensive property) and it depends both will give same amount of heat because the surface available for heat transfer is greater in case of the kettle as well as the heat stored in it but if you talk.....
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about the amount of heat stored in the system then in that case since the mass of water in the kettle is greater so more energy is required to raise the temperature b/c more molecules of water are present in the kettle
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definitely of physics
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what is field
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physics, biology and chemistry this is my Field
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field is a region of space under the influence of some physical properties
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No. According to Isac Newtons law. this two bodies maybe you and the wall beside you. Attracting depends on the mass och each body and distance between them.
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Are you really asking if two bodies have to be charged to be influenced by Coulombs Law?
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What is specific heat capacity
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specific heat capacity is the amount of energy needed to raise the temperature of a substance by one degree Celsius or kelvin
ROKEEB
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Source:  OpenStax, Introductory statistics. OpenStax CNX. May 06, 2016 Download for free at http://legacy.cnx.org/content/col11562/1.18
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