document.write( "Question 1197417: Sun Courier - a parcel delivery company - has found that the delivery time of parcels
\n" ); document.write( "to clients in Durban metropolitan area after airport collection is normally distributed
\n" ); document.write( "with a mean delivery time equal to 45 minutes and a standard deviation of 8 minutes.
\n" ); document.write( "For a newly arrived consignment at Durban airport, what is the probability that a
\n" ); document.write( "randomly selected parcel will take:
\n" ); document.write( "a. Between 45 and 51 minutes to deliver to the client?
\n" ); document.write( "b. Less than 48 minutes to deliver?
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Algebra.Com's Answer #830674 by Theo(13342)\"\" \"About 
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z = (x - m) / s
\n" ); document.write( "z is the z-score
\n" ); document.write( "x is the raw score
\n" ); document.write( "m is the mean
\n" ); document.write( "s is the standard deviation.
\n" ); document.write( "you have:
\n" ); document.write( "m = 45
\n" ); document.write( "s = 8
\n" ); document.write( "when x = 45, z = (45 - 45) / s = 0
\n" ); document.write( "when x = 51, z = (51 - 45) / s = 6 / 8 = 3/4 = .75
\n" ); document.write( "area to the left of z = 0 = .5
\n" ); document.write( "area to the left of z = .75 = .7734 rounded to 4 decimal places.
\n" ); document.write( "area in between z = 0 and z = .75 = .7734 - .5 = .2734.
\n" ); document.write( "that's the probability that the package will take between 45 and 51 minutes to deliver to the client. \r
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\n" ); document.write( "\n" ); document.write( "when x = 48, z = (x - m) / s becomes z = (48 - 45) / 8 which becomes z = 3 / 8 = .375.
\n" ); document.write( "area to the left of z = .375 = .6462 rounded to 4 decimal places.
\n" ); document.write( "that's the probability that the package will take less than 48 minutes to deliver to the client.\r
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