document.write( "Question 473929: Help!!!
\n" ); document.write( "A class has 17 boys and 10 girls. One student is selected. F is the event of selecting a girl, and K is the event of selecting Kate, one of the girls in the class. Determine
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Algebra.Com's Answer #325051 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
P(K | F) literally means (in English): \"the probability of selecting Kate given a girl/female was selected\". I underlined \"given\" for emphasis to show that we know 100% that a girl was selected.\r
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\n" ); document.write( "\n" ); document.write( "So if we know that a girl was selected, then what is the probability that Kate is chosen.\r
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\n" ); document.write( "\n" ); document.write( "Take note that there are 10 girls, and only one Kate (assuming we're talking about a specific and unique \"Kate\"). So the probability is \"1%2F10\"\r
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\n" ); document.write( "\n" ); document.write( "P(K | F) = \"1%2F10\"\r
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\n" ); document.write( "\n" ); document.write( "In decimal form, \"1%2F10=0.1\", so \r
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\n" ); document.write( "\n" ); document.write( "P(K | F) = 0.1\r
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\n" ); document.write( "\n" ); document.write( "Is another way to say it. Note: 0.1 is 10%\r
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\n" ); document.write( "\n" ); document.write( "Further notes....\r
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\n" ); document.write( "\n" ); document.write( "If the notation P(K | F) confuses you, then think of P(K | F) as P(K) given that F has occurred (or is true). \r
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\n" ); document.write( "\n" ); document.write( "P(F | K) is very similar, but asks the reverse: \"What is the probability of selecting a female GIVEN that Kate has been chosen?\"\r
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\n" ); document.write( "\n" ); document.write( "Well, we know that Kate is a girl (since this is a natural assumption to make and because it's stated in the question). So because Kate was chosen and that she is a girl, we can say that the probability is 1 (basically 1 refers to 100%). In other words, if we know that Kate was selected, then the person MUST be a female.\r
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\n" ); document.write( "\n" ); document.write( "So P(F | K) = 1\r
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