document.write( "Question 1149744: The cost of two ice cream cones is $2.25. A mother had in her a purse exactly two $2 coins, two $1 coins and two quarters. She took out two coins at random to pay for the coins. What is the probability that she did NOT have at least $2.25? \n" ); document.write( "

Algebra.Com's Answer #771080 by math_helper(2461) $\"\"$ $\"About$

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document.write( "There are nine possible outcomes:\r
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document.write( "(in cents):
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document.write( "25 and 25      x
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document.write( "25 and 100     x 
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document.write( "25 and 200 
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document.write( "100 and 25     x
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document.write( "100 and 100    x
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document.write( "100 and 200
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document.write( "200 and 25
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document.write( "200 and 100
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document.write( "200 and 200          \r
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document.write( "Only the four outcomes marked with an x add to less than 225 (= $2.25)\r
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document.write( "We can not say P(sum < 225) = 4/9, however, because not all the listed outcomes are equally likely.  Here are the probabilities for the marked outcomes:\r
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document.write( "25 and 25      1/15 
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document.write( "25 and 100     2/15
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document.write( "100 and 25     2/15
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document.write( "100 and 100    1/15
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document.write( "               ----
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document.write( "               6/15 =    or 40%\r
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