document.write( "Question 1193219: I have done i,ii,iii just need v but unsure if right \r
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document.write( "The random variable 𝑋 is given by the sum of the scores when two ordinary dice are thrown. For this experiment:
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document.write( "i) Write down the sample space 𝑆.
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document.write( "ii) Draw a table to show the probability distribution and the cumulative
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document.write( "distribution of 𝑋.
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document.write( "iii) Write down the probability function of 𝑋.
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document.write( "iv) Draw a vertical line graph to illustrate the probability distribution of 𝑋(with probability on the y-axis and 𝑋- values on the x-axis) and describe the shape of the distribution. (You may use excel or simply draw by hand on paper)
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document.write( "v) Evaluate the following. You must show your working (you may use Excel where possible to show working)
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document.write( "1. 𝑃(𝑋>8)
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document.write( "2. 𝑃(|𝑋−7|<3)
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document.write( "3. 𝐸(𝑋)
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document.write( "4. 𝑉𝑎𝑟(𝑋)\r
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document.write( "A.i)
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document.write( "Dices 1 2 3 4 5 6
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document.write( "1 1,1 1,2 1,3 1,4 1,5 1,6
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document.write( "2 2,1 2,2 2,3 2,4 2,5 2,6
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document.write( "3 3,1 3,2 3,3 3,4 3,5 3,6
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document.write( "4 4,1 4,2 4,3 4,4 4,5 4,6
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document.write( "5 5,1 5,2 5,3 5,4 5,5 5,6
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document.write( "6 6,1 6,2 6,3 6,4 6,5 6,6 sample space = 36\r
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document.write( "ii. X 1 2 3 4 5 6
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document.write( " P(X=x) 1/36 3/36 5/36 7/36 9/36 11/36
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document.write( " P(x) 1/36 4/36 9/36 16/36 25/36 1\r
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document.write( "iii.
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document.write( "P(X=x) {1/36 x = 1
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document.write( " 3/36 x = 2
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document.write( " 5/36 x = 3
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document.write( " 7/36 x = 4
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document.write( " 9/36 x = 5
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document.write( " 11/36 x = 6. this right ??\r
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document.write( "v. is here but unsure if is right\r
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document.write( " 7 8 9 10 11 12
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document.write( "v. 13/36 15/36 17/36 19/36 21/36 23/36
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document.write( "1 𝑃(𝑋>8) = P ( X≥9) F(9) =2.25 49/36=1.36 64/36=1.78 81/36=2.25 100/36=2.78 121/36=3.36 144/36=4
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document.write( "2 𝑃(|𝑋−7|<3)
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document.write( "3 𝐸(𝑋)= 10.63 x p(x) xp(x) x^2 p(x) (x-m)^2P(X)
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document.write( " or 4.472 1 0.027 0.27 0.03
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document.write( "4 Var(x) =71.001216 2 0.11 0.22 0.44
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document.write( " 1^2=1 3 0.25 0.75 2.25
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document.write( " 2^2=4 4 0.44 1.76 7.04
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document.write( " 3^2=9 5 0.69 3.45 17.25
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document.write( " 4^2=16 6 1 6 36
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document.write( " 5^2=25 ∑p(x)=2.52 ∑xp(x)=10.63 ∑x^2p(x) = 63.01
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document.write( " 6^2=36
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document.write( " 91-4.472^2 \n" );
document.write( "
Algebra.Com's Answer #825249 by ikleyn(52781)![]() ![]() You can put this solution on YOUR website! .\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Hey, I looked at your post, and I see that parts (ii) and (iii) are solved incorrectly.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "I think that you don't know relevant theory.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "From the other side, I see your intention to do the job on your own, which I like very much.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So, my advise to you is to read a lesson\r \n" ); document.write( "\n" ); document.write( " - Rolling a pair of fair dice \r \n" ); document.write( "\n" ); document.write( "in this site. You will find there many other similar solved problems.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "After reading it, you will be able to solve the mentioned parts in a correct way, I believe.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "When you redo and complete the parts (ii) and (iii) on your own, you may re-post your solution to this forum (to me) for checking.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "///////////////\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "David, I got your comment.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Your error in parts (ii) and (iii) is that you consider X as a variable for single separate throw, \r \n" ); document.write( "\n" ); document.write( "while the problem DEFINES X as the sum of values, when a pair of dice is thrown.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So, do not argue with me . . . // If your desire to argue with me prevails your desire to learn, then you are not my customer . . . \r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "You better READ the lesson which I recommended you.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "It is written SPECIALLY for those individuals who care about developing their mind, their skills and their knowledge.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "I will be glad to contact with you later, when I see your progress.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |