document.write( "Question 214655: If you increase your rate by 25 mph and you are going 25 miles you get there 10 min earlier, what was your initial rate? \n" ); document.write( "
Algebra.Com's Answer #162096 by stanbon(75887)\"\" \"About 
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If you increase your rate by 25 mph and you are going 25 miles you get there 10 min earlier, what was your initial rate?
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\n" ); document.write( "Initial DATA:
\n" ); document.write( "distance = 25 miles ; rate = x mph ; time = d/r = 25/x hrs.
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\n" ); document.write( "Modified DATA:
\n" ); document.write( "distance = 25 miles ; rate = (x+25) mph ; time = d/r = 25/(x+25) hrs.
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\n" ); document.write( "Equation:
\n" ); document.write( "old time - new time = 1/6 hr
\n" ); document.write( "25/x - 25/(x+25) = 1/6
\n" ); document.write( "---
\n" ); document.write( "6*25(x+25) - 6*25x = x(x+25)
\n" ); document.write( "150x + 6*625 - 150x = x^2 + 25x
\n" ); document.write( "x^2 + 25x - 6*625 = 0
\n" ); document.write( "(x-50)(x+75) = 0
\n" ); document.write( "Positive solution:
\n" ); document.write( "x = 50 mph (initial rate)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "
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