document.write( "Question 703785: 
Determine whether each of the distributions given below represents a probability distribution.    Justify your answer.\r\n" );
document.write( "please walk me through this\r\n" );
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document.write( "(A)\r\n" );
document.write( "x    P(x)\r\n" );
document.write( "1    1/5\r\n" );
document.write( "2    9/25\r\n" );
document.write( "3    2/5\r\n" );
document.write( "4    1/25\r\n" );
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document.write( "(B)\r\n" );
document.write( "x   P(x)\r\n" );
document.write( "3   0.7\r\n" );
document.write( "6   1/12\r\n" );
document.write( "8   0.22\r\n" );
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document.write( "(C) \r\n" );
document.write( " x    P(x)\r\n" );
document.write( "20   13/25\r\n" );
document.write( "30    0.25\r\n" );
document.write( "40   -0.01\r\n" );
document.write( "50    6/25
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Algebra.Com's Answer #433698 by AnlytcPhil(1807)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "We have to check just two requirements:\r\n" );
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document.write( "(1)   All the probabilities in the P(x)\r\n" );
document.write( "list must be between 0 and 1 inclusive.\r\n" );
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document.write( "(2)   The sum of the probabilities in\r\n" );
document.write( "the P(x) list must equal to 1.\r\n" );
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document.write( "(A)\r\n" );
document.write( "x    P(x)\r\n" );
document.write( "1    1/5\r\n" );
document.write( "2    9/25\r\n" );
document.write( "3    2/5\r\n" );
document.write( "4    1/25\r\n" );
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document.write( "It meets the requirements of (1). Let's\r\n" );
document.write( "check requirement (2) \r\n" );
document.write( "\"1%2F5%2B9%2F25%2B2%2F5%2B1%2F25\"\r\n" );
document.write( "Get LCD of 25\r\n" );
document.write( "\"5%2F25%2B9%2F25%2B10%2F25%2B1%2F25\" =\r\n" );
document.write( "\"25%2F25\" = 1, so yes it is a\r\n" );
document.write( "probability distribution.\r\n" );
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document.write( "(B)\r\n" );
document.write( "x   P(x)\r\n" );
document.write( "3   0.7\r\n" );
document.write( "6   1/12\r\n" );
document.write( "8   0.22\r\n" );
document.write( "It meets the requirements of (1). Let's\r\n" );
document.write( "check requirement (2) \r\n" );
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document.write( "\"0.7%2B1%2F12%2B0.22\"\r\n" );
document.write( "Change the decimals to fractions \r\n" );
document.write( "\"7%2F10%2B1%2F12%2B22%2F100\" \r\n" );
document.write( "Get LCD of 300\r\n" );
document.write( "\"210%2F300%2B25%2F300%2B66%2F300\"\r\n" );
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document.write( "\"301%2F300\" ≠ 1, so NO it is NOT a\r\n" );
document.write( "probability distribution.\r\n" );
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document.write( "(C) \r\n" );
document.write( " x    P(x)\r\n" );
document.write( "20   13/25\r\n" );
document.write( "30    0.25\r\n" );
document.write( "40   -0.01\r\n" );
document.write( "50    6/25\r\n" );
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document.write( "It does NOT meet requirement (1), because of\r\n" );
document.write( "the negative number in the probability list,\r\n" );
document.write( "so it is NOT a probability distribution\r\n" );
document.write( "function.\r\n" );
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document.write( "Edwin
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