document.write( "Question 360068: In testing a new drug, researchers found that 20% of all patients using it will have a mild side effect. A random sample of 13 patients using the drug is selected. Find the probability that:
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\n" ); document.write( "(A) exactly three will have this mild side effect
\n" ); document.write( "(B) at least five will have this mild side effect.\r
\n" ); document.write( "\n" ); document.write( "Binomial Problem with n=13; p=0.20
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\n" ); document.write( "P(x=3)=0.20^3\r
\n" ); document.write( "\n" ); document.write( "I am not sure if I am on the right track with this? \n" ); document.write( "

Algebra.Com's Answer #256948 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!


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document.write( "Hi,
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document.write( "Binomial Problem with n=13; p=0.20  Yes, you are on the right track there.\r
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document.write( "Note: The probability of x successes in n trials is: \r
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document.write( "P = nCx* * where p and q are the probabilities of success and failure respectively.
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document.write( "In this case p(mild side effect)=.2 & q =.8 
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document.write( "nCx = \r
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document.write( "(A) exactly three will have this mild side effect
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document.write( "P(3 with mild side effects) = 13C3* *
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document.write( "13C3 = 13!/3!10! = 13*12*11/3*2 = 286
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document.write( "P(3 with mild side effects) = 286* *\r
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document.write( "(B) at least five will have this mild side effect. 
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document.write( "1-   P(0)   + P(1)       + P(2)             + P(3)         + P(4) 
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document.write( "1 - .8^13 + 13*.2^1.8^12 + 78*.2^2.8^11 + 286*.2^3.8^10 + 715*.2^4.8^9 \n" );
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