document.write( "Question 1059726: reyna has 5 coins worth 10 cents each and 4 coins worth 25 cents each. if she choose two of these coons at random, what is the probability that the two coins together will be worth at least 35 cents? \n" ); document.write( "

Algebra.Com's Answer #674769 by Fombitz(32388) $\"\"$ $\"About$

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Let D be the 10 cent coin, let Q be the 25 cent coin.
\n" ); document.write( "Look at the possible outcomes of a two coin draw and the sums,
\n" ); document.write( "DD=>20
\n" ); document.write( "DQ=>35
\n" ); document.write( "QD=>35
\n" ); document.write( "QQ=>50
\n" ); document.write( "Look at the probability of each outcome (I wont simplify until the final answer),
\n" ); document.write( "DD: $\"P=%285%2F9%29%284%2F8%29=20%2F72\"$
\n" ); document.write( "DQ: $\"P=%285%2F9%29%284%2F8%29=20%2F72\"$
\n" ); document.write( "QD: $\"P=%284%2F9%29%285%2F9%29=20%2F72\"$
\n" ); document.write( "QQ: $\"P=%284%2F9%29%283%2F8%29=12%2F72\"$
\n" ); document.write( "When you sum the probabilities, they add up to 1 so all possible outcomes are covered.
\n" ); document.write( "So for at least 35, sum the probabilities where the sum is at least 35.
\n" ); document.write( " $\"P=%2820%2B20%2B12%29%2F72=52%2F72=13%2F18\"$
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