document.write( "Question 1199907: 66% of all violent felons in the prison system are repeat offenders. If 45 violent felons are randomly selected, find the probability that
\n" ); document.write( "( I just need help on letter C, the rest I got them correct)
\n" ); document.write( "a. Exactly 29 of them are repeat offenders.
\n" ); document.write( "0.1205286384
\n" ); document.write( "Correct\r
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\n" ); document.write( "\n" ); document.write( "b. At most 29 of them are repeat offenders.
\n" ); document.write( "0.4682375156
\n" ); document.write( "Correct\r
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\n" ); document.write( "\n" ); document.write( "c. At least 30 of them are repeat offenders. ?\r
\n" ); document.write( "\n" ); document.write( "d. Between 27 and 31 (including 27 and 31) of them are repeat offenders.
\n" ); document.write( "0.553313931
\n" ); document.write( "Correct
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Algebra.Com's Answer #833887 by math_tutor2020(3817)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "I'll focus on part (c) only.\r
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\n" ); document.write( "\n" ); document.write( "For questions like this, you could calculate by hand.
\n" ); document.write( "However that is tedious busy-work in my opinion. The reason why I say this is because you would have 16 separate calculations, each of which are somewhat long in their own right.\r
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\n" ); document.write( "\n" ); document.write( "It's better to use a specialized binomial distribution calculator such as this one
\n" ); document.write( "https://www.gigacalculator.com/calculators/binomial-probability-calculator.php
\n" ); document.write( "In this case:
\n" ); document.write( "n = 45 = sample size
\n" ); document.write( "p = 0.66 = probability of a repeat offender
\n" ); document.write( "x = 30 = number of repeat offenders
\n" ); document.write( "Look for where it says \"Probability of X ≥ 30 events\".\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "If you want to use your TI83 or TI84 calculator, then refer to this page for more information
\n" ); document.write( "https://www.statology.org/binomial-probabilities-ti-84-calculator/
\n" ); document.write( "Focus on the binomialcdf function and NOT the binomialpdf.
\n" ); document.write( "That page explains how to find the binomialcdf function. Also there are examples.\r
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\n" ); document.write( "\n" ); document.write( "Something like
\n" ); document.write( "binomialcdf(45,0.66,29)
\n" ); document.write( "will calculate the sum of the probability values from x = 0 to x = 29\r
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\n" ); document.write( "\n" ); document.write( "Subtract that from 1 to find the sum of the probabilities from x = 30 to x = 45.\r
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\n" ); document.write( "\n" ); document.write( "This is valid because
\n" ); document.write( "P(0 ≤ X ≤ 29) + P(30 ≤ X ≤ 45) = 1 \r
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\n" ); document.write( "\n" ); document.write( "Therefore you'll type into the TI83 or TI84 calculator 1-binomialcdf(45,0.66,29) to find the probability of having at least 30 repeat offenders.
\n" ); document.write( "Be careful to avoid typing in 1-binomialcdf(45,0.66,30) as that would slightly be off.\r
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\n" ); document.write( "\n" ); document.write( "If instead you want to use a spreadsheet, then the command is called BINOMDIST
\n" ); document.write( "https://support.microsoft.com/en-us/office/binomdist-function-506a663e-c4ca-428d-b9a8-05583d68789c\r
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\n" ); document.write( "\n" ); document.write( "There are many other options.\r
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\n" ); document.write( "\n" ); document.write( "Let me know if you have any questions about a particular piece of software, website, spreadsheet, or calculator. \r
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\n" ); document.write( "\n" ); document.write( "Hint about the final answer: It is between 0.5 and 0.6
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