document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1061377>Question 1061377</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find x to make the ratios form a proportion<BR>\n" );
document.write( "With checking\r<BR>\n" );
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document.write( "1.) 12 : 7 = x : 21\r<BR>\n" );
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document.write( "2.) 3/2 : 4/3 = x : 7/6\r<BR>\n" );
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document.write( "3.) x : 12 = 5 : 8\r<BR>\n" );
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document.write( "4.) 7 : 9 = 49 : x </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #676162 by </B><A HREF=/tutors/aboutme.mpl?userid=HelpfulBro><B>HelpfulBro(2)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=HelpfulBro><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=676162\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1. 12 : 7 = x : 21 can also be written as fractions:<BR>\n" );
document.write( "12/7 = x/21\r<BR>\n" );
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document.write( "Next step is to cross multiply and solve for x:<BR>\n" );
document.write( "( 12 * 21 ) = ( 7 * x)<BR>\n" );
document.write( "252 = 7x\r<BR>\n" );
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document.write( "To isolate x, we divide 7 to both sides of the equation:<BR>\n" );
document.write( "252/7 = 7x/7\r<BR>\n" );
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document.write( "x=36\r<BR>\n" );
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document.write( "TO CHECK, WE SUBSTITUTE THE VALUE OF X IN THE PROBLEM:<BR>\n" );
document.write( "12/7 = 36/21\r<BR>\n" );
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document.write( "Once again, we cross multiply.\r<BR>\n" );
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document.write( "12*21 = 7 * 36<BR>\n" );
document.write( "252 = 252\r<BR>\n" );
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document.write( "SAME PROCESS APPLIES TO ALL THE OTHER PROBLEMS.\r<BR>\n" );
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document.write( "2.) 3/2 : 4/3 = x : 7/6 \r<BR>\n" );
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document.write( "for this number, we'll have to simplify them first.<BR>\n" );
document.write( " 3/2 : 4/3 would be simplified as 9/8; as for <BR>\n" );
document.write( " x : 7/6 , it would be 6x/7\r<BR>\n" );
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document.write( "now that they're simplified, we can now write our eqn as:<BR>\n" );
document.write( "9/8 = 6x/7\r<BR>\n" );
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document.write( "We solve the problem applying the same process we did on number 1<BR>\n" );
document.write( "9/8 = 6x/7<BR>\n" );
document.write( "63 = 48 x<BR>\n" );
document.write( "63/48 = x<BR>\n" );
document.write( "21/16 = x\r<BR>\n" );
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document.write( "CHECKING:\r<BR>\n" );
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document.write( "3/2 : 4/3 = x : 7/6 <BR>\n" );
document.write( "9/8 = 6x/7<BR>\n" );
document.write( "9/8 = [6*(21/16)] / 7<BR>\n" );
document.write( "9/8 = (63/8) / 7<BR>\n" );
document.write( "9/8 = 63/56<BR>\n" );
document.write( "9/8 = 9/8<BR>\n" );
document.write( "72 = 72\r<BR>\n" );
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document.write( "3.) x : 12 = 5 : 8 <BR>\n" );
document.write( "X/12 = 5/8<BR>\n" );
document.write( "8X = 12 * 5<BR>\n" );
document.write( "8X = 60<BR>\n" );
document.write( "X = 15/2\r<BR>\n" );
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document.write( "CHECKING:\r<BR>\n" );
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document.write( "(15/2)/12 = 5 / 8<BR>\n" );
document.write( "15 / 24 = 5 / 8 <BR>\n" );
document.write( "8*15 = 24*5<BR>\n" );
document.write( "120 = 120 \r<BR>\n" );
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document.write( "4) 7 : 9 = 49 : x<BR>\n" );
document.write( "7/9 = 49/X<BR>\n" );
document.write( "7x = 441<BR>\n" );
document.write( "x = 63\r<BR>\n" );
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document.write( "CHECKING:<BR>\n" );
document.write( "7/9 = 49/63<BR>\n" );
document.write( "7*63 = 9*49<BR>\n" );
document.write( "441 = 441\r<BR>\n" );
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document.write( "Hope this helps xD\r<BR>\n" );
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document.write( " </SPAN>\n" );
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