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Sue travels 5 mph less than twice as fast as June. Starting at the same point and traveling in the same direction, they are 80 miles apart after 4 hours. Find their speeds.
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\n" ); document.write( "Let x = J's speed
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\n" ); document.write( "It says, \"Sue travels 5 mph less than twice as fast as June.\" So we can say:
\n" ); document.write( "(2x - 5) = S's speed
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\n" ); document.write( "Using the statement: \"Starting at the same point and traveling in the same
\n" ); document.write( " direction, they are 80 miles apart after 4 hours.\" we can say:
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\n" ); document.write( "S's dist traveled - J's distance traveled = 80
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\n" ); document.write( "Dist = Time * speed
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\n" ); document.write( "4(2x-5) - 4x = 80
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\n" ); document.write( "8x - 20 - 4x = 80
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\n" ); document.write( "8x - 4x = 80 + 20; added 20 to both sides:
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\n" ); document.write( "4x = 100
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\n" ); document.write( "x = 100/4
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\n" ); document.write( "x = 25mph is J's speed
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\n" ); document.write( "Using (2x - 5)
\n" ); document.write( "2(25) - 5 =
\n" ); document.write( "50 - 5 = 45 mph is S's speed
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\n" ); document.write( "Check our solution by finding the distance that each has traveled:
\n" ); document.write( "S: 4(45) = 180 mi
\n" ); document.write( "J: 4(25) = 100 mi
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\n" ); document.write( "Difference: 80 mi
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\n" ); document.write( "How about this? Did this method seem understandable to you? Any questions \n" ); document.write( "