document.write( "Question 617139: Okay so I'm completely stuck on this problem. How do I go about figuring out whether they are of the probability distribution? \r
\n" ); document.write( "\n" ); document.write( "Can you show me a step-by-step?\r
\n" ); document.write( "\n" ); document.write( "6. Determine whether each of the distributions given below represents a probability distribution. Justify your answer.
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\n" ); document.write( "A)
\n" ); document.write( " x | 1 2 3 4
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\n" ); document.write( "P(x)| 3/16 3/8 1/4 3/16\r
\n" ); document.write( "\n" ); document.write( "B)
\n" ); document.write( " x | 3 6 8
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\n" ); document.write( "P(x)| 0.11 21/25 0.06\r
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\n" ); document.write( "C)
\n" ); document.write( " x | 20 30 40 50
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\n" ); document.write( "P(x)| 11/20 0.15 1/5 0.1\r
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Algebra.Com's Answer #388160 by Edwin McCravy(20086) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "Add up all the probabilities and see if they are all positive,\r\n" );
document.write( "between 0 and 1 and have a sum of EXACTLY 1.\r\n" );
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document.write( "A)\r\n" );
document.write( "   x |  1    2   3   4\r\n" );
document.write( " ------------------------\r\n" );
document.write( " P(x)| 3/16 3/8 1/4 3/16\r\n" );
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document.write( "Ther are all positive between 0 and 1.  Let's add them:\r\n" );
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document.write( "They have sum exactly 1, so this is a discrete probability distribution.\r\n" );
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document.write( "B) \r\n" );
document.write( "   x |   3    6     8\r\n" );
document.write( " ----------------------\r\n" );
document.write( " P(x)| 0.11 21/25 0.06\r\n" );
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document.write( "They are all positive between 0 and 1.  Let's add them:\r\n" );
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document.write( "Those probabilities do not have sum exactly 1, so it is not a probability disturibution.\r\n" );
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document.write( "C) \r\n" );
document.write( "   x |   20   30  40   50\r\n" );
document.write( " -----------------------------\r\n" );
document.write( " P(x)| 11/20 0.15 1/5 0.1\r\n" );
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document.write( "They are all positive between 0 and 1.  Let's add them: \r\n" );
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document.write( "11/20 +0.15 +1/5+ 0.1 = 11/20 + 15/100 +1/5 +1/10 = 55/100+15/100+20/10010/100 = 100/100 = 1}}}\r\n" );
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document.write( "They have sum exactly 1, so this is a discrete probability distribution.\r\n" );
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document.write( "Edwin

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