document.write( "Question 126254: A person traveling 4 hour by plane and 25 hour by ship covers 1580 miles. If the speed of the plane had been one-half of the actual speed and speed of the ship had been one-fourth greater, the person would have traveled only 1315 miles in the same length of time. Find the speeds of the plane and the ship. \n" ); document.write( "
Algebra.Com's Answer #92619 by ankor@dixie-net.com(22740)\"\" \"About 
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A person traveling 4 hour by plane and 25 hour by ship covers 1580 miles. If the speed of the plane had been one-half of the actual speed and speed of the ship had been one-fourth greater, the person would have traveled only 1315 miles in the same length of time. Find the speeds of the plane and the ship.
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\n" ); document.write( "Originally
\n" ); document.write( "Let x = speed of the plane (mph)
\n" ); document.write( "Let y = speed of the ship
\n" ); document.write( "If:
\n" ); document.write( ".5x = speed of the plane
\n" ); document.write( "1.25y = speed of the ship
\n" ); document.write( ":
\n" ); document.write( "Write two distance equations: Distance = time * speed
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\n" ); document.write( "Actual event equation:
\n" ); document.write( "4x + 25y = 1580
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\n" ); document.write( "If event equation:
\n" ); document.write( "4(.5x) + 25(1.25y)
\n" ); document.write( "2x + 31.25y = 1315
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\n" ); document.write( "Use elimination here. Multiple above equation by 2, subtract \"Actual\" equation:
\n" ); document.write( "4x + 62.5y = 2630
\n" ); document.write( "4x + 25y = 1580
\n" ); document.write( "-------------------Subtracting eliminates x
\n" ); document.write( "0x + 37.5y = 1050
\n" ); document.write( "y = \"1050%2F37.5\"
\n" ); document.write( "y = 28 mph is the ships original speed
\n" ); document.write( ":
\n" ); document.write( "Use equation; 4x + 25y = 1580; substitute 28 for y:
\n" ); document.write( "4x + 25(28) = 1580
\n" ); document.write( "4x = 700 = 1580
\n" ); document.write( "4x = 1580 - 700
\n" ); document.write( "4x = 880
\n" ); document.write( "x = \"880%2F4\"
\n" ); document.write( "x = 220 mph plane's original speed
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\n" ); document.write( ":
\n" ); document.write( "Check our solutions in the \"If event\" equation
\n" ); document.write( "4(.5(220)) + 25(1.25(28)) =
\n" ); document.write( "440 + 875 = 1315
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