document.write( "Question 1198592: a) A random variable x has a binomial distribution with n = 12.
\n" ); document.write( "Given that p = 0.25, find\r
\n" ); document.write( "\n" ); document.write( "(i) p (x < 5) (From table III or IV of Appendix A)\r
\n" ); document.write( "\n" ); document.write( "(ii) p (x ≥ 7) (From table III or IV of Appendix A)\r
\n" ); document.write( "\n" ); document.write( "b)Given that p(x=0) = 0.05, find the value of p to 3 decimal places.
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Algebra.Com's Answer #848414 by ElectricPavlov(122)\"\" \"About 
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**a) Binomial Distribution with n = 12 and p = 0.25**\r
\n" ); document.write( "\n" ); document.write( "* **(i) p(x < 5)**\r
\n" ); document.write( "\n" ); document.write( " * Using a binomial probability table or calculator (like the one provided in the code response), we find:
\n" ); document.write( " * p(x < 5) = 0.8819\r
\n" ); document.write( "\n" ); document.write( "* **(ii) p(x ≥ 7)**\r
\n" ); document.write( "\n" ); document.write( " * p(x ≥ 7) = 1 - p(x < 7)
\n" ); document.write( " * Using a binomial probability table or calculator, we find:
\n" ); document.write( " * p(x < 7) = 0.9856
\n" ); document.write( " * Therefore, p(x ≥ 7) = 1 - 0.9856 = 0.0144\r
\n" ); document.write( "\n" ); document.write( "**b) Finding the value of p given p(x=0) = 0.05**\r
\n" ); document.write( "\n" ); document.write( "* We know that for a binomial distribution:
\n" ); document.write( " * p(x=0) = (nCx) * p^x * (1-p)^(n-x)
\n" ); document.write( " * where nCx is the binomial coefficient (number of combinations of n items taken x at a time)\r
\n" ); document.write( "\n" ); document.write( "* In this case, n = 12 and x = 0
\n" ); document.write( " * p(x=0) = (12C0) * p^0 * (1-p)^(12-0)
\n" ); document.write( " * p(x=0) = 1 * 1 * (1-p)^12 \r
\n" ); document.write( "\n" ); document.write( "* We are given p(x=0) = 0.05
\n" ); document.write( " * Therefore, 0.05 = (1-p)^12\r
\n" ); document.write( "\n" ); document.write( "* Solve for p:
\n" ); document.write( " * p = 1 - (0.05)^(1/12)
\n" ); document.write( " * p ≈ 0.221\r
\n" ); document.write( "\n" ); document.write( "**Therefore:**\r
\n" ); document.write( "\n" ); document.write( "* **a) (i) p(x < 5) = 0.8819**
\n" ); document.write( " * **(ii) p(x ≥ 7) = 0.0144**
\n" ); document.write( "* **b) The value of p is approximately 0.221**
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