document.write( "Question 204368: if A:c=1:3 and b:c=5:7,find a:b and a:b:c. \n" ); document.write( "
Algebra.Com's Answer #154292 by RAY100(1637)\"\" \"About 
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a/b=a/c*c/b = 1/3 * 7/5 = 7/15
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\n" ); document.write( "a/b/c,, a/b=7/15,,,and b/c =5/7 or 15/21,,therefore a/b/c = 7/15/21
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\n" ); document.write( "look at it as a/b and b/c ,,,7:15,,,and 15:21,,,or 7:15:21
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