document.write( "Question 805074: The waiting time at an elevator is uniformly distributed between 30 and 200 seconds. What is the probability a rider must wait between 1 minute and 1.5 minutes?
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\n" ); document.write( "A. 0.1765
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\n" ); document.write( "C. 0.5294
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\n" ); document.write( "D. 0.8824
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Algebra.Com's Answer #485074 by Edwin McCravy(20062)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "The uniform distribution is a rectangular shaped distribution. It\r\n" );
document.write( "is a rectangle that has a base 200-30 = 170 seconds long and an area \r\n" );
document.write( "of 1, which represents a probability of 1 that they will wait no less\r\n" );
document.write( "than 30 seconds nor more than 200 seconds.  \r\n" );
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document.write( "    A = b·h\r\n" );
document.write( "    1 = 170·h\r\n" );
document.write( "1/170 = h\r\n" );
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document.write( "Think of it as this rectangle\r\n" );
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document.write( " ______________________\r\n" );
document.write( "|______________________|  height = 1/170 units\r\n" );
document.write( "   base = 170 seconds\r\n" );
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document.write( "The probability that a rider must wait between 1 minute and 1.5 minutes\r\n" );
document.write( "is just a slice of this rectangle whose base is between 1 minute and\r\n" );
document.write( "1.5 minutes which is 1.5-1 = .5 minutes or 30 seconds.\r\n" );
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document.write( "Such a slice might look like this:\r\n" );
document.write( " __\r\n" );
document.write( "|__|  height = 1/170 units\r\n" );
document.write( "base = 30 seconds\r\n" );
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document.write( "The area of this slice would be base·height = 30·(1/170) = .1765\r\n" );
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document.write( "Edwin
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