document.write( "Question 488990: If I drop three coins on a table, what is the probability of finding
\n" ); document.write( " 1. exactly 2 heads
\n" ); document.write( " 2. at most 1 head
\n" ); document.write( " 3. at least 2 heads
\n" ); document.write( " 4. at least 1 head
\n" ); document.write( "sample space = 8\r
\n" ); document.write( "\n" ); document.write( "I came up with HHT, HTH, THH,HTT,THT,TTH,TTT,HHH.
\n" ); document.write( "state the probability of each in the form of fraction and percent.
\n" ); document.write( "For 1,2,3 I came up with 1/4 or .25, and for 4 = 1/6.
\n" ); document.write( "Have I done this correctly, or can you show me a better way to show this??
\n" ); document.write( "Is this a form of \"classical probability\"??
\n" ); document.write( "Thank you. \n" ); document.write( "
Algebra.Com's Answer #852351 by ikleyn(52879)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "If I drop three coins on a table, what is the probability of finding
\n" ); document.write( "1. exactly 2 heads
\n" ); document.write( "2. at most 1 head
\n" ); document.write( "3. at least 2 heads
\n" ); document.write( "4. at least 1 head
\n" ); document.write( "sample space = 8
\n" ); document.write( "I came up with HHT, HTH, THH,HTT,THT,TTH,TTT,HHH.
\n" ); document.write( "state the probability of each in the form of fraction and percent.
\n" ); document.write( "For 1,2,3 I came up with 1/4 or .25, and for 4 = 1/6.
\n" ); document.write( "Have I done this correctly, or can you show me a better way to show this??
\n" ); document.write( "Is this a form of \"classical probability\"??
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\n" ); document.write( "\n" ); document.write( "        As I read the problem and your solution in your post,\r
\n" ); document.write( "\n" ); document.write( "        it becomes clear to me that your level is  introductory  in  Probability.\r
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\n" ); document.write( "\n" ); document.write( "        At this level,  the problem assumes that you will prepare the space of events\r
\n" ); document.write( "\n" ); document.write( "        and will answer questions based on this table,  without using the combinatorics terms/formulas\r
\n" ); document.write( "\n" ); document.write( "        of  Binomial distribution, as tutor  @Theo does.\r
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\n" ); document.write( "\n" ); document.write( "        So,  I  will not demonstrate how smart  I  am,  but simply will prepare the table of events\r
\n" ); document.write( "\n" ); document.write( "        and will show you how to operate with it.\r
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document.write( "The events are in the second column of this table below.\r\n" );
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document.write( "It has 8 elements, so the space of events has 8 elements with associated probability \r\n" );
document.write( "1/8 for each event.\r\n" );
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document.write( "           Q1    Q2    Q3    Q4\r\n" );
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document.write( "  1  HHH                *     *\r\n" );
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document.write( "  2  HHT    *           *     *\r\n" );
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document.write( "  3  HTH    *           *     *\r\n" );
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document.write( "  4  HTT          *           *\r\n" );
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document.write( "  5  THT          *           *\r\n" );
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document.write( "  6  TTH          *           *\r\n" );
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document.write( "  7  TTT          *         \r\n" );
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document.write( "  8  THH    *           *     *\r\n" );
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document.write( "For Question 1, I marked by (*) 3 appropriate events in column Q1.\r\n" );
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document.write( "                So, the probability P(Q1) = 3/8.\r\n" );
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document.write( "For Question 2, I marked by (*) 4 appropriate events in column Q2.\r\n" );
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document.write( "                As a reminder, \"at most 1 head\" means 0 or 1 heads.\r\n" );
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document.write( "                So, the probability P(Q2) = 4/8 = 1/2.\r\n" );
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document.write( "For Question 3, I marked by (*) 4 appropriate events in column Q3.\r\n" );
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document.write( "                As a reminder, \"at least 2 heads\" means 2 or 3 heads.\r\n" );
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document.write( "                So, the probability P(Q3) = 4/8 = 1/2.\r\n" );
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document.write( "For Question 4, I marked by (*) 7 appropriate events in column Q4.\r\n" );
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document.write( "                As a reminder, \"at least 1 head\" means 1 or 2 or 3 heads.\r\n" );
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document.write( "                So, the probability P(Q4) = 7/8.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.   All questions are answered.\r
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\n" ); document.write( "\n" ); document.write( "So,  at this level  (which is  YOUR  level),  it is  HOW  TO  you should analyze this problem,\r
\n" ); document.write( "\n" ); document.write( "how to you should solve this problem and how to you should present your solution.\r
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\n" ); document.write( "\n" ); document.write( "It is what your teacher does expect from you.\r
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