document.write( "Question 1144816: A student number system for a county requires that the student number be 5 characters. The first 3 characters are any single digit number, but no number can repeat and the last 2 characters must be letters, but no letter can repeat. How many unique student numbers are possible?\r
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document.write( "A. 1,370\r
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document.write( "B. 131,040\r
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document.write( "C. 250,000\r
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document.write( "D. 468,000\r
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document.write( "Is D correct?\r
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document.write( "The question and the answer choices in the link here: https://prnt.sc/p3ubbd \n" );
document.write( "
Algebra.Com's Answer #765987 by jim_thompson5910(35256)![]() ![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "We have 5 slots to fill. Let's call them A,B,C,D,E\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The first three slots (A,B,C) are a single digit number. We have 10 choices for slot A, 9 for B, and 8 for C. So far we have 10*9*8 = 720 different ways to form a three digit number where the digits do not repeat. It's possible to select 0 first. \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "For slot D, we have 26 letters to pick from. For slot E, we have 25 letters left over. So we have 26*25 = 650 different two letter combos (repeat not allowed)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Multiply the two sub-results and we end up with: 720*650 = 468,000\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Choice D is the correct answer.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "As shorthand you can simply multiply everything out as such \n" ); document.write( "10*9*8*26*25 = 468,000 \n" ); document.write( " \n" ); document.write( " |