document.write( "Question 1193100: A survey shows that about 70 % of those over the age of 65 years old are in danger of catching COVID-19. If 7 persons over the age of 65 are randomly selected, answer the following questions:
\n" ); document.write( "A) What is the probability exactly 4 of the 7 have COVID-19?
\n" ); document.write( "b.) What is the probability at most 1 of the 7 has COVID-19?
\n" ); document.write( "c.) What is the probability at least 2 of the 7 have COVID-19?
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Algebra.Com's Answer #825094 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "A survey shows that about 70 % of those over the age of 65 years old
\n" ); document.write( "are in danger of catching COVID-19.
\n" ); document.write( "If 7 persons over the age of 65 are randomly selected, answer the following questions:
\n" ); document.write( "a) What is the probability exactly 4 of the 7 have COVID-19?
\n" ); document.write( "b) What is the probability at most 1 of the 7 has COVID-19?
\n" ); document.write( "c) What is the probability at least 2 of the 7 have COVID-19?
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\n" ); document.write( "\n" ); document.write( " These are standard problems on binomial distribution.\r
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document.write( "(a) - number of trials         n =  7;\r\n" );
document.write( "    - number of success trials k =  4;\r\n" );
document.write( "    - Probability of success on a single trial p = 0.7.\r\n" );
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document.write( "      P =  =  = 0.2269  (rounded).    ANSWER\r\n" );
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document.write( "(b) - number of trials         n =  7;\r\n" );
document.write( "    - number of success trials k <= 1;   (k = 0, 1)\r\n" );
document.write( "    - Probability of success on a single trial p = 0.7.\r\n" );
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document.write( "      Use online free of charge calculator https://stattrek.com/online-calculator/binomial.aspx\r\n" );
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document.write( "          P = P(n=7; k<=1; p=0.7) = 0.003791  (rounded).    ANSWER\r\n" );
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document.write( "(c) - number of trials         n =  7;\r\n" );
document.write( "    - number of success trials k >= 2;   (k = 2,3,4,5,6,7)\r\n" );
document.write( "    - Probability of success on a single trial p = 0.7.\r\n" );
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document.write( "\r\n" );
document.write( "      You may use online free of charge calculator https://stattrek.com/online-calculator/binomial.aspx\r\n" );
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document.write( "          P = P(n=7; k>=2; p=0.7) = 0.9962  (rounded), \r\n" );
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document.write( "      or simply notice that this probability is the complement to that found in part (b)\r\n" );
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document.write( "          P = 1 - 0.003791 = 0.9962  (the same value).    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "If you want to see many similar or different solved problems on binomial distribution probability, look into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Simple and simplest probability problems on Binomial distribution \r
\n" ); document.write( "\n" ); document.write( "    - Typical binomial distribution probability problems \r
\n" ); document.write( "\n" ); document.write( "    - How to calculate Binomial probabilities with Technology (using MS Excel) \r
\n" ); document.write( "\n" ); document.write( "    - Solving problems on Binomial distribution with Technology (using MS Excel) \r
\n" ); document.write( "\n" ); document.write( "    - Solving problems on Binomial distribution with Technology (using online solver) \r
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\n" ); document.write( "\n" ); document.write( "After reading these lessons, you will be able to solve such problems on your own, \r
\n" ); document.write( "\n" ); document.write( "which is your PRIMARY MAJOR GOAL visiting this forum (I believe).\r
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