document.write( "Question 1111045: A doctor knows from experience that 18% of the patients to whom she gives a certain drug will have undesirable side effects. Among the 9 patients to whom she gives the drug, find the following probabilities. (Give your answers correct to three decimal places.)
\n" ); document.write( "(a) Find the probability P(At most two will have undesirable side effects).
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\n" ); document.write( "\n" ); document.write( "(b) Find the probability P(At least two will have undesirable side effects).
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Algebra.Com's Answer #726057 by KMST(5328)\"\" \"About 
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The probability of one patient having undesirable side effects is
\n" ); document.write( "\"%2218%25%22=0.18\" .
\n" ); document.write( "The probability of one patient not having undesirable side effects is
\n" ); document.write( "\"1-0.18=0.82\" .
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\n" ); document.write( "In a binomial distribution,
\n" ); document.write( "the probabilities of exactly 0, 1, and 2 out of 9 patients having undesirable side effects
\n" ); document.write( "would be the coefficients of the first three terms of
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\n" ); document.write( "The first term is the probability of exactly 0 patients having undesirable side effects.
\n" ); document.write( "Rounding, it is
\n" ); document.write( "\"0.82%5E9=0.16762=%2216.762%25%22\" .
\n" ); document.write( "The second term represents the probability of exactly 1 patients having undesirable side effects.
\n" ); document.write( "Rounding, its coefficient is
\n" ); document.write( "\"9%2A0.82%5E8%2A0.18=0.33115=%2233.115%25%22\" .
\n" ); document.write( "The third term represents the probability of exactly 2 patients having undesirable side effects.
\n" ); document.write( "Rounding, its coefficient is
\n" ); document.write( "\"36%2A0.8%5E7%2A0.18%5E2=0.29077=%2229.077%25%22\" .
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\n" ); document.write( "(a) P(At most two will have undesirable side effects) =\"0.16762%2B0.33115%2B0.29077=0.78954=%2278.954%25%22\" .
\n" ); document.write( "Presumably the teacher wants the probability as a decimal,
\n" ); document.write( "and the answer \"correct to three decimal places\" would be
\n" ); document.write( "\"highlight%28%220.790%22%29\" .
\n" ); document.write( "We can tell the doctor that
\n" ); document.write( "P(At most two will have undesirable side effects) =\"highlight%28%2279.0%25%22%29\" .
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\n" ); document.write( "(b) P(Less than 2 patients having undesirable side effects)
\n" ); document.write( "= P(no undesirable side effects) + P(exactly one patient having undesirable side effects)
\n" ); document.write( "\"%22=%22\"\"0.16762%2B0.33115=0.49877\" .
\n" ); document.write( "The opposite of that is 2 or more patients having undesirable side effects,
\n" ); document.write( "or \"at least two\" patients having undesirable side effects, so
\n" ); document.write( "P(At least two will have undesirable side effects) \"%22=%22\"\"1-0.49877=0.50123\" .
\n" ); document.write( "the answer \"correct to three decimal places\" would be
\n" ); document.write( "\"highlight%28%220.501%22%29\" .
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