document.write( "Question 178064: Chris and Jan drove a total of 618 miles in 12.8 hours. Chris drove the first part of the trip and averaged 35 miles per hour. Jan drove the remainder of the trip and averaged 55 miles per hour. For what length of the time did Chris drive? \n" ); document.write( "
Algebra.Com's Answer #133081 by ankor@dixie-net.com(22740)\"\" \"About 
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Chris and Jan drove a total of 618 miles in 12.8 hours. Chris drove the first
\n" ); document.write( " part of the trip and averaged 35 miles per hour. Jan drove the remainder of
\n" ); document.write( " the trip and averaged 55 miles per hour. For what length of the time did Chris drive?
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\n" ); document.write( "let t = length time Chris drove
\n" ); document.write( "then
\n" ); document.write( "(12.8-t) = length time Jan drove
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\n" ); document.write( "write a dist equation: dist = speed * time
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\n" ); document.write( "C's drive dist + J's drive dist = 618
\n" ); document.write( "35t + 55(12.8-t) = 618
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\n" ); document.write( "35t + 704 - 55t = 618
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\n" ); document.write( "35t - 55t = 618 - 704
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\n" ); document.write( "-20t = -86
\n" ); document.write( "t = \"%28-86%29%2F%28-20%29\"
\n" ); document.write( "t = +4.3 hrs Chris drove
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\n" ); document.write( "Check solution:
\n" ); document.write( "J's time: 12.8 - 4.3 = 8.5 hrs
\n" ); document.write( "35(4.3) + 55(8.5) =
\n" ); document.write( "150.5 + 467.5 = 618 \n" ); document.write( "
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