document.write( "Question 1157599: how many numbers greater than 150 can be formed from the digit 1,2,3,4,5 if no repetitions allowed \n" ); document.write( "
Algebra.Com's Answer #780494 by Edwin McCravy(20081)\"\" \"About 
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document.write( "Case 1. The number has 3 digits and the first digit is 1.\r\n" );
document.write( "There are only three, 152, 153, and 154\r\n" );
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document.write( "Case 2: The number has 3 digits and the first digit is not 1.\r\n" );
document.write( "(They will all be greater than 150.)\r\n" );
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document.write( "We can choose the first digit 4 ways, (2,3,4,or 5).  \r\n" );
document.write( "We can choose the second digit 4 ways.\r\n" );
document.write( "We can choose the third digit 3 ways.\r\n" );
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document.write( "That's 4∙4∙3 = 48\r\n" );
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document.write( "Case 3: The number has 4 digits. \r\n" );
document.write( "(They will all be greater than 150.)\r\n" );
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document.write( "We can choose the first digit 5 ways.\r\n" );
document.write( "We can choose the second digit 4 ways.\r\n" );
document.write( "We can choose the third digit 3 ways.\r\n" );
document.write( "We can choose the fourth digit 2 ways.  \r\n" );
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document.write( "That's 5∙4∙3∙2 = 120\r\n" );
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document.write( "Case 4: The number has 5 digits. \r\n" );
document.write( "(They will all be greater than 150.)\r\n" );
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document.write( "We can choose the first digit 5 ways.\r\n" );
document.write( "We can choose the second digit 4 ways.\r\n" );
document.write( "We can choose the third digit 3 ways.\r\n" );
document.write( "We can choose the fourth digit 2 ways.  \r\n" );
document.write( "We can choose the fifth digit 1 way.\r\n" );
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document.write( "That's 5∙4∙3∙2∙1 = 120\r\n" );
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document.write( "Total for all 4 cases: 3+48+120+120 = 291\r\n" );
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document.write( "Edwin
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