document.write( "Question 276144: An automobile averaged 45 mph for the first part of a trip and 50 mph for the second part. If the entire trip took 4hr and covered 195 mi, for how long was the rate 45 mph? \n" ); document.write( "
Algebra.Com's Answer #201306 by ankor@dixie-net.com(22740)\"\" \"About 
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An automobile averaged 45 mph for the first part of a trip and 50 mph for the second part.
\n" ); document.write( " If the entire trip took 4hr and covered 195 mi, for how long was the rate 45 mph?
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\n" ); document.write( "Let x = time at 45 mph
\n" ); document.write( "then
\n" ); document.write( "(4-x) = time at 50 mph
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\n" ); document.write( "Write a distance equation: dist = speed * time
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\n" ); document.write( "45mph dist + 50 mph dist = 195 mi
\n" ); document.write( "45x + 50(4-x) = 195
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\n" ); document.write( "45x + 200 - 50x = 195
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\n" ); document.write( "45x - 50x = 195 - 200
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\n" ); document.write( "-5x = -5
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\n" ); document.write( "x = 1 hr at 45 mph
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\n" ); document.write( "Check solution (3hr at 50mph)
\n" ); document.write( "45(1) + 50(3) = 195 \n" ); document.write( "
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