document.write( "Question 331603: When designing the placement of a CD player in a new model car, engineers must consider the forward grip reach of the driver. Women have forward grip reaches that are normally distributed with a mean of 27.0 inches and a standard deviation of 1.3 inches.Use the 68-95-99.7 rule to find:
\n" ); document.write( "A) The percentage of women with forward grip reaches between 24.4 inches and 29.6 inches.
\n" ); document.write( "B) Find the percentage of women with forward grip reaches less than 30.9 inches.
\n" ); document.write( "C) Find the percentage of women with forward grip reaches between 27.0 inches and 28.3 inches.
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Algebra.Com's Answer #237747 by jrfrunner(365)\"\" \"About 
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Given Normally distributed data with mean=27.0 and standard deviation =1.3
\n" ); document.write( "1 standard deviation = 1.3
\n" ); document.write( "2 standard deviations=2.6
\n" ); document.write( "3 standard deviations =3.9
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\n" ); document.write( "A) The percentage of women with forward grip reaches between 24.4 inches and 29.6 inches.\r
\n" ); document.write( "\n" ); document.write( "compute the mid-range
\n" ); document.write( "Upper value-Xbar =29.6-27.0=2.6
\n" ); document.write( "Xbar - Lower value =27.0-24.4=2.6
\n" ); document.write( "This means that 24.4 to 29.6 is 2 standard deviations from the mean
\n" ); document.write( "approximately 95% of the data will lie within 2 standard dev from the mean
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\n" ); document.write( "B) Find the percentage of women with forward grip reaches less than 30.9 inches.
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\n" ); document.write( "compute the distance in standard deviations from the mean to the largest value\r
\n" ); document.write( "\n" ); document.write( "30.9-27.0 = 3.9 this is 3 standard deviations above the mean
\n" ); document.write( "1/2 of 99.7% of the data will lie within the mean and 3 standard deviations
\n" ); document.write( "50% of the data will lie below the mean
\n" ); document.write( "so, the answer is 50% + 1/2*99.7% =99.85%
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\n" ); document.write( "C) Find the percentage of women with forward grip reaches between 27.0 inches and 28.3 inches.
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\n" ); document.write( "compute the distance which starts at the mean 27.0 and goes to 28.3
\n" ); document.write( "28.3-27.0=1.3 this is one standard deviation above the mean\r
\n" ); document.write( "\n" ); document.write( "Since approx 68% of the data lies within 1 standard deviation on either side of the maan, the answer is 1/2* 68% = 34%\r
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