document.write( "Question 62072: Please help me solve this homework problem. The least common multiple of 2 numbers is 3780, and the greatest common factor is 18. Given that one of the numbers is 180, what is the other number?\r
\n" ); document.write( "\n" ); document.write( "I started out by 3780/180= 21. But 18 is not a factor of 21? What am I doing wrong?
\n" ); document.write( "Thanks!
\n" ); document.write( "Laura
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Algebra.Com's Answer #42833 by joyofmath(189)\"\" \"About 
You can put this solution on YOUR website!
The least common multiple of 2 numbers is 3780, and the greatest common factor is 18. Given that one of the numbers is 180, what is the other number?\r
\n" ); document.write( "\n" ); document.write( "To solve these GCF and LCM problems, factor the numbers you're working with into primes:\r
\n" ); document.write( "\n" ); document.write( "3780 = 2*2*3*3*3*5*7
\n" ); document.write( "180 = 2*2*3*3*5\r
\n" ); document.write( "\n" ); document.write( "We know that the LCM of the two numbers, call them A and B, = 3780 and that A = 180. The greatest common factor of 180 and B = 18 so B has factors 2*3*3 in common with 180 but no other factors in common with 180. So, B has no more 2's and no 5's.
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\n" ); document.write( "Now, LCM(180,B) = 3780. So, A or B must have each of the factors of 3780. B needs another factor of 3 and a factor of 7 since LCM(A,B) needs for either A or B to have a factor of 2*2, which A has, and a factor of 3*3*3, which B will have with another factor of 3, and a factor of 7, which B will have.\r
\n" ); document.write( "\n" ); document.write( "So, B = 2*3*3*3*7 = 378.
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\n" ); document.write( "Here's a website that calculates GCF and LCM for you that you can use to verify the answer.
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\n" ); document.write( "http://www.venturaes.com/coolstuff/GCF_LCM.html
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