document.write( "Question 1109901: bobby left the space museum and drove south nancy left three hours later driving 42 km/h faster in an effort to catch up to him after two hours nancy finally caught up find bobby's average speed
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Algebra.Com's Answer #724878 by greenestamps(13208) $\"\"$ $\"About$

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\n" ); document.write( "Nancy had to drive only 2 hours to catch up to Bobby, who drove for 5 hours. Since the distances were the same and the ratio of times was 2:5, the ratio of speeds was 5:2.

\n" ); document.write( "Let Bobby's speed by 2x and Nancy's speed be 5x. Nancy's speed is 42km/h faster than Bobby's:
\n" ); document.write( " $\"5x-2x=42\"$
\n" ); document.write( " $\"3x=42\"$
\n" ); document.write( " $\"x+=+14\"$

\n" ); document.write( "Bobby's speed was 2x = 28km/hr; Nancy's was 5x = 70km/hr. \n" ); document.write( "

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