document.write( "Question 878463: Mike's Resume shop specializes in creating resumes for students. A recent survey of Mike's shop revealed that a spelling error was made on 10% of the resumes last year. Calculate the probabilities that a certain number of resumes have spelling errors assuming this rate continues into this year and they prepare 8315 resumes.
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Algebra.Com's Answer #530117 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( "Below You will find a  similar workup
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document.write( "p(error) = .10,  n = 8315, mean = 831.5 and SD = sqrt(831.5*.90) = 27.356
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document.write( "Use 840.5  and 839.5 as shown below
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document.write( "Stattrek.com gives a).371  b) .629  c) .014
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document.write( "doing the work will give You the 4 decimal points
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document.write( "...........................................................................
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document.write( "I.  recommend using a TI Calculator...
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document.write( "II. Must Learn when to recognize a Binomial Distribution, when You see one.
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document.write( "Most recognizable when You see a % of a certain event given.  Generally when samples are very Large(>1000), 
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document.write( "one uses a normal approximation to the binomial.
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document.write( "Trick is: When Using the normal approxiamation, one uses 'endpoints' (using .5)
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document.write( "a)p(error) = .10,  n = 5370, mean = 537 and SD = sqrt(537*.90) = 21.98
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document.write( "P(x > 530) = 1 - P(z ≤ (  - 537)/21.98 = 1- P(z ≤-.2957) = 1 - .3837= .6163
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document.write( "b) P(x ≤ 530) = P(z ≤ -.2957) = .3837
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document.write( "c) P(x = 530) = P(z ≤ -.2957)-P(z ≤ (  - 537)/21.98 =.3837 - .3665 = .0172
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document.write( "Again, while it is not to 4 decimal points.. one can verify this using stattrek.com (Binomial distributions)
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document.write( "If Using TI...Using syntax: normalcdf(smaller, larger, ľ, σ).
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document.write( "normalcdf(-9999, 530.5, 537, 21.98) and normal(-9999,529.5,537, 21.98)
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document.write( "would have made short work of this
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document.write( "Note: The -9999 is used as the smaller value to be at least 5 standard deviations from the mean. \n" );
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