document.write( "Question 1197565: A pair of 6 sided dice are tossed. What is the probability that at least one of the dice has a value greater than or equal to 5? \n" ); document.write( "
Algebra.Com's Answer #830873 by math_tutor2020(3816)\"\" \"About 
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\n" ); document.write( "There are 6 sides on each dice, giving 6*6 = 36 outcomes.\r
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\n" ); document.write( "\n" ); document.write( "Let's call the dice A and B
\n" ); document.write( "Let's have die A roll to 4 or smaller. Same goes for die B.
\n" ); document.write( "There are 4*4 = 16 outcomes where both dice are 4 or smaller.\r
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\n" ); document.write( "\n" ); document.write( "That must mean 36-16 = 20 outcomes are when either
\n" ); document.write( "A = 5 or 6
\n" ); document.write( "OR
\n" ); document.write( "B = 5 or 6
\n" ); document.write( "or both scenarios happen\r
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\n" ); document.write( "\n" ); document.write( "We can confirm this with a chart
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123456
1XX
2XX
3XX
4XX
5XXXXXX
6XXXXXX
The 'X's represent the situation when either dice is 5 or larger (i.e. 5 or 6) \r
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\n" ); document.write( "\n" ); document.write( "There are 6 X's in row 5 and 6 X's in row 6
\n" ); document.write( "That's 6+6 = 12 X's total so far.
\n" ); document.write( "We have 6 X's in column 5 and 6 X's in column 6
\n" ); document.write( "That's another 6+6 = 12 X's
\n" ); document.write( "We're up to 12+12 = 24 \r
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\n" ); document.write( "\n" ); document.write( "But in the bottom right hand corner, we're double counting those four X's since they are in the overlapped region of the four columns mentioned.
\n" ); document.write( "We need to subtract off 4 to correct for this erroneous double counting.
\n" ); document.write( "24-4 = 20\r
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\n" ); document.write( "\n" ); document.write( "Or note that the blank portion of the table is 4 rows tall and 4 columns across.
\n" ); document.write( "This represents the 4*4 = 16 cases where both dice are 4 or smaller, as mentioned earlier.
\n" ); document.write( "This then gives us the 36-16 = 20 copies of X in total.\r
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\n" ); document.write( "\n" ); document.write( "The summary so far is that there are 20 ways to have at least one of the dice be 5 or 6.\r
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\n" ); document.write( "\n" ); document.write( "This is out of 36 ways to roll two dice
\n" ); document.write( "20/36 = (4*5)/(4*9) = 5/9\r
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\n" ); document.write( "\n" ); document.write( "Answer: 5/9
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