document.write( "Question 107632: Tina can run 12 mi in the same time it takes her to bicycle
\n" ); document.write( "72 mi. If her bicycling rate is 20 mi/h faster than her running rate, find each
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Algebra.Com's Answer #78449 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Tina can run 12 mi in the same time it takes her to bicycle
\n" ); document.write( "72 mi. If her bicycling rate is 20 mi/h faster than her running rate, find each
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\n" ); document.write( "Let s = T's running speed
\n" ); document.write( "then
\n" ); document.write( "(s+20) = T's cycling speed
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\n" ); document.write( "Run time = cycling time
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\n" ); document.write( "Time = Dist/speed
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\n" ); document.write( "\"12%2Fs\" = \"72%2F%28%28s%2B20%29%29\"
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\n" ); document.write( "Cross multiply:
\n" ); document.write( "72s = 12(s+20)
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\n" ); document.write( "72s = 12s + 240
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\n" ); document.write( "72s - 12s = 240
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\n" ); document.write( "60s = 240
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\n" ); document.write( "s = 240/60
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\n" ); document.write( "s = 4 mph is T's running speed
\n" ); document.write( "Then
\n" ); document.write( "24 mph is T's cycling speed
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\n" ); document.write( "Check solution by find the times:
\n" ); document.write( "12/4 = 3 hrs
\n" ); document.write( "72/24 = 3 hrs, confirms our solutions
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